[Title 40 CFR ]
[Code of Federal Regulations (annual edition) - July 1, 2010 Edition]
[From the U.S. Government Printing Office]
[[Page 1]]
40
Parts 136 to 149
Revised as of July 1, 2010
Protection of Environment
________________________
Containing a codification of documents of general
applicability and future effect
As of July 1, 2010
With Ancillaries
Published by
Office of the Federal Register
National Archives and Records
Administration
A Special Edition of the Federal Register
[[Page ii]]
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[[Page iii]]
Table of Contents
Page
Explanation................................................. v
Title 40:
Chapter I--Environmental Protection Agency
(Continued) 3
Finding Aids:
Table of CFR Titles and Chapters........................ 931
Alphabetical List of Agencies Appearing in the CFR...... 951
List of CFR Sections Affected........................... 961
[[Page iv]]
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Cite this Code: CFR
To cite the regulations in
this volume use title,
part and section number.
Thus, 40 CFR 136.1 refers
to title 40, part 136,
section 1.
----------------------------
[[Page v]]
EXPLANATION
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[[Page vi]]
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[[Page vii]]
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July 1, 2010.
[[Page ix]]
THIS TITLE
Title 40--Protection of Environment is composed of thirty-two
volumes. The parts in these volumes are arranged in the following order:
parts 1-49, parts 50-51, part 52 (52.01-52.1018), part 52 (52.1019-end
of part 52), parts 53-59, part 60 (60.1-end of part 60, sections), part
60 (Appendices), parts 61-62, part 63 (63.1-63.599), part 63 (63.600-
63.1199), part 63 (63.1200-63.1439), part 63 (63.1440-63.6175), part 63
(63.6580-63.8830), part 63 (63.8980-end of part 63) parts 64-71, parts
72-80, parts 81-84, part 85-Sec. 86.599-99, part 86 (86.600-1-end of
part 86), parts 87-99, parts 100-135, parts 136-149, parts 150-189,
parts 190-259, parts 260-265, parts 266-299, parts 300-399, parts 400-
424, parts 425-699, parts 700-789, parts 790-999, and part 1000 to end.
The contents of these volumes represent all current regulations codified
under this title of the CFR as of July 1, 2010.
Chapter I--Environmental Protection Agency appears in all thirty-two
volumes. Regulations issued by the Council on Environmental Quality,
including an Index to Parts 1500 through 1508, appear in the volume
containing part 1000 to end. The OMB control numbers for title 40 appear
in Sec. 9.1 of this chapter.
For this volume, Cheryl E. Sirofchuck, was Chief Editor. The Code of
Federal Regulations publication program is under the direction of
Michael L. White, assisted by Ann Worley.
[[Page 1]]
TITLE 40--PROTECTION OF ENVIRONMENT
(This book contains parts 136 to 149)
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Part
chapter i--Environmental Protection Agency (Continued)...... 136
[[Page 3]]
CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
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Editorial Note: Nomenclature changes to chapter I appear at 65 FR
47324, 47325, Aug. 2, 2000, and at 66 FR 34375, 34376, June 28, 2001.
SUBCHAPTER D--WATER PROGRAMS (CONTINUED)
Part Page
136 Guidelines establishing test procedures for
the analysis of pollutants.............. 5
140 Marine sanitation device standard........... 363
141 National primary drinking water regulations. 367
142 National primary drinking water regulations
implementation.......................... 639
143 National secondary drinking water
regulations............................. 697
144 Underground injection control program....... 702
145 State UIC program requirements.............. 768
146 Underground injection control program:
Criteria and standards.................. 781
147 State, tribal, and EPA-administered
underground injection control programs.. 813
148 Hazardous waste injection restrictions...... 915
149 Sole source aquifers........................ 924
[[Page 5]]
SUBCHAPTER D_WATER PROGRAMS (CONTINUED)
PART 136_GUIDELINES ESTABLISHING TEST PROCEDURES FOR THE ANALYSIS OF POLLUTANTS--Table of Contents
Sec.
136.1 Applicability.
136.2 Definitions.
136.3 Identification of test procedures.
136.4 Application for alternate test procedures.
136.5 Approval of alternate test procedures.
136.6 Method modifications and analytical requirements.
Appendix A to Part 136--Methods for Organic Chemical Analysis of
Municipal and Industrial Wastewater
Appendix B to Part 136--Definition and Procedure for the Determination
of the Method Detection Limit--Revision 1.11
Appendix C to Part 136--Inductively Coupled Plasma--Atomic Emission
Spectrometric Method for Trace Element Analysis of Water and
Wastes Method 200.7
Appendix D to Part 136--Precision and Recovery Statements for Methods
for Measuring Metals
Authority: Secs. 301, 304(h), 307 and 501(a), Pub. L. 95-217, 91
Stat. 1566, et seq. (33 U.S.C. 1251, et seq.) (the Federal Water
Pollution Control Act Amendments of 1972 as amended by the Clean Water
Act of 1977).
Sec. 136.1 Applicability.
(a) The procedures prescribed herein shall, except as noted in Sec.
136.5, be used to perform the measurements indicated whenever the waste
constituent specified is required to be measured for:
(1) An application submitted to the Administrator, or to a State
having an approved NPDES program for a permit under section 402 of the
Clean Water Act of 1977, as amended (CWA), and/or to reports required to
be submitted under NPDES permits or other requests for quantitative or
qualitative effluent data under parts 122 to 125 of title 40, and,
(2) Reports required to be submitted by dischargers under the NPDES
established by parts 124 and 125 of this chapter, and,
(3) Certifications issued by States pursuant to section 401 of the
CWA, as amended.
(b) The procedure prescribed herein and in part 503 of title 40
shall be used to perform the measurements required for an application
submitted to the Administrator or to a State for a sewage sludge permit
under section 405(f) of the Clean Water Act and for recordkeeping and
reporting requirements under part 503 of title 40.
[72 FR 14224, Mar. 26, 2007]
Sec. 136.2 Definitions.
As used in this part, the term:
(a) Act means the Clean Water Act of 1977, Pub. L. 95-217, 91 Stat.
1566, et seq. (33 U.S.C. 1251 et seq.) (The Federal Water Pollution
Control Act Amendments of 1972 as amended by the Clean Water Act of
1977).
(b) Administrator means the Administrator of the U.S. Environmental
Protection Agency.
(c) Regional Administrator means one of the EPA Regional
Administrators.
(d) Director means the Director of the State Agency authorized to
carry out an approved National Pollutant Discharge Elimination System
Program under section 402 of the Act.
(e) National Pollutant Discharge Elimination System (NPDES) means
the national system for the issuance of permits under section 402 of the
Act and includes any State or interstate program which has been approved
by the Administrator, in whole or in part, pursuant to section 402 of
the Act.
(f) Detection limit means the minimum concentration of an analyte
(substance) that can be measured and reported with a 99% confidence that
the analyte concentration is greater than zero as determined by the
procedure set forth at appendix B of this part.
[38 FR 28758, Oct. 16, 1973, as amended at 49 FR 43250, Oct. 26, 1984]
Sec. 136.3 Identification of test procedures.
(a) Parameters or pollutants, for which methods are approved, are
listed together with test procedure descriptions and references in
Tables IA, IB, IC, ID, IE, IF, IG, and IH. In the event
[[Page 6]]
of a conflict between the reporting requirements of 40 CFR Parts 122 and
125 and any reporting requirements associated with the methods listed in
these tables, the provisions of 40 CFR Parts 122 and 125 are controlling
and will determine a permittee's reporting requirements. The full text
of the referenced test procedures are incorporated by reference into
Tables IA, IB, IC, ID, IE, IF, IG, and IH. The incorporation by
reference of these documents, as specified in paragraph (b) of this
section, was approved by the Director of the Federal Register in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies of the
documents may be obtained from the sources listed in paragraph (b) of
this section. Documents may be inspected at EPA's Water Docket, EPA
West, 1301 Constitution Avenue, NW., Room B102, Washington, DC
(Telephone: 202-566-2426); or at the National Archives and Records
Administration (NARA). For information on the availability of this
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/
federal--register/code--of--federal--regulations/ibr--locations.html.
These test procedures are incorporated as they exist on the day of
approval and a notice of any change in these test procedures will be
published in the Federal Register. The discharge parameter values for
which reports are required must be determined by one of the standard
analytical test procedures incorporated by reference and described in
Tables IA, IB, IC, ID, IE, IF, IG, and IH or by any alternate test
procedure which has been approved by the Administrator under the
provisions of paragraph (d) of this section and Sec. Sec. 136.4 and
136.5. Under certain circumstances paragraph (c) of this section, Sec.
136.5(a) through (d) or 40 CFR 401.13, other additional or alternate
test procedures may be used.
[[Page 7]]
Table IA--List of Approved Biological Methods for Wastewater and Sewage Sludge
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Standard methods
Parameter and units Method \1\ EPA 18th, 19th, 20th Standard methods AOAC, ASTM, USGS Other
ed. online
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Bacteria:
1. Coliform (fecal), number Most Probable p. 132 \3\........ 9221 C E.......... 9221 C E-99.......
per 100 mL or number per Number (MPN),\5\ 1680 \12,14\......
gram dry weight. tube 3 dilution, 1681 \12,19\......
or
Membrane filter p. 124 \3\........ 9222 D............ 9222 D-97......... B-0050-85 \5\.....
(MF) \2\, single
step.
2. Coliform (fecal) in MPN, 5 tube, 3 p. 132 \3\........ 9221 C E.......... 9221 C E-99.......
presence of chlorine, dilution, or
number per 100 mL.
MF \2\, single p. 124 \3\........ 9222 D............ 9222 D-97.........
step.
3. Coliform (total), number MPN, 5 tube, 3 p. 114 \3\........ 9221 B............ 9221 B-99.........
per 100 mL. dilution, or
MF \2\, single p. 108 \3\........ 9222 B............ 9222 B-97......... B-0025-8 \5\......
step or two step.
4. Coliform (total), in MPN, 5 tube, 3 p. 114 \3\........ 9221 B............ 9221 B-99.........
presence of chlorine, dilution, or
number per 100 mL.
MF \2\ with p. 111 \3\........ 9222 (B+B.5c)..... 9222 (B+B.5c)-97..
enrichment.
5. E. coli, number per 100 MPN \7,9,15\ .................. 9223 B \13\....... 9223 B-97 \13\.... 991.15 \11\....... Colilert[reg]\13,1
mL \20\. multiple tube/ 7\
multiple well. Colilert-
18[reg]\13,16,17\
MF \2,6,7,8,9\ 1603 \21\......... .................. .................. .................. mColiBlue-
single step. 24[reg]\18\
6. Fecal streptococci, MPN, 5 tube 3 p. 139 \3\........ 9230 B............ 9230 B-93.........
number per 100 mL. dilution,.
MF \2\, or........ p. 136 \3\........ 9230 C............ 9230 C-93......... B-0055-85 \5\.....
Plate count....... p. 143 \3\........
7. Enterococci, number per MPN \7,9\, .................. .................. .................. D6503-99 \10\..... Enterolert[reg]
100 mL \20\. multiple tube/ \13,23\
multiple well.
MF \2,6,7,8,9\ 1600 \24\.........
single step.
8. Salmonella, number per MPN multiple tube. 1682 \22\.........
gram dry weight \12\.
Aquatic Toxicity:
9. Toxicity, acute, fresh Ceriodaphnia dubia 2002.0 \25\.......
water organisms, LC 50, acute.
percent effluent.
Daphnia puplex and 2021.0 \25\.......
Daphnia magna
acute.
Fathead Minnow, 2000.0 \25\.......
Pimephales
promelas, and
Bannerfin shiner,
Cyprinella
leedsi, acute.
Rainbow Trout, 2019.0 \25\.......
Oncorhynchus
mykiss, and brook
trout, Salvelinus
fontinalis, acute.
[[Page 8]]
10. Toxicity, acute, Mysid, Mysidopsis 2007.0 \25\.......
estuarine and marine bahia, acute.
organisms of the Atlantic
Ocean and Gulf of Mexico,
LC50, percent effluent.
Sheepshead Minnow, 2004.0 \25\.......
Cyprinodon
variegatus, acute.
Silverside, 2006.0 \25\.......
Menidia
beryllina,
Menidia menidia,
and Menidia
peninsulae, acute.
11. Toxicity, chronic, fresh Fathead minnow, 1000.0 \26\.......
water organisms, NOEC or Pimephales
IC25, percent effluent. promelas, larval
survival and
growth.
Fathead minnow, 1001.0 \26\.......
Pimephales
promelas, embryo-
larval survival
and
teratogenicity.
Daphnia, 1002.0 \26\.......
Ceriodaphnia
dubia, survival
and reproduction.
Green alga, 1003.0 \26\.......
Selenastrum
capricornutum,
growth.
12. Toxicity, chronic, Sheepshead minnow, 1004.0 \27\.......
estuarine and marine Cyprinodon
organisms of the Atlantic variegatus,
Ocean and Gulf of Mexico, larval survival
NOEC or IC25, percent and growth.
effluent.
Sheepshed minnow, 1005.0 \27\.......
Cyprinodon
variegatus,
embryo-larval
survival and
teratogenicity.
Inland silverside, 1006.0 \27\.......
Menidia
beryllina, larval
survival and
growth.
Mysid, Mysidopsis 1007.0 \27\.......
bahia, survival,
growth, and
fecundity.
Sea urchin, 1008.0 \27\.......
Arbacia
punctulata,
fertilization.
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\1\ The method must be specified when results are reported.
\2\ A 0.45 [mu]m membrane filter (MF) or other pore size certified by the manufacturer to fully retain organisms to be cultivated and to be free of
extractables which could interfere with their growth.
\3\ USEPA. 1978. Microbiological Methods for Monitoring the Environment, Water, and Wastes. Environmental Monitoring and Support Laboratory, U.S.
Environmental Protection Agency, Cincinnati, OH, EPA/600/8-78/017.
\4\ [Reserved]
[[Page 9]]
\5\ USGS. 1989. U.S. Geological Survey Techniques of Water-Resource Investigations, Book 5, Laboratory Analysis, Chapter A4, Methods for Collection and
Analysis of Aquatic Biological and Microbiological Samples, U.S. Geological Survey, U.S. Department of the Interior, Reston, VA.
\6\ Because the MF technique usually yields low and variable recovery from chlorinated wastewaters, the Most Probable Number method will be required to
resolve any controversies.
\7\ Tests must be conducted to provide organism enumeration (density). Select the appropriate configuration of tubes/filtrations and dilutions/volumes
to account for the quality, character, consistency, and anticipated organism density of the water sample.
\8\ When the MF method has been used previously to test waters with high turbidity, large numbers of noncoliform bacteria, or samples that may contain
organisms stressed by chlorine, a parallel test should be conducted with a multiple-tube technique to demonstrate applicability and comparability of
results.
\9\ To assess the comparability of results obtained with individual methods, it is suggested that side-by-side tests be conducted across seasons of the
year with the water samples routinely tested in accordance with the most current Standard Methods for the Examination of Water and Wastewater or EPA
alternate test procedure (ATP) guidelines.
\10\ ASTM. 2000, 1999, 1996. Annual Book of ASTM Standards--Water and Environmental Technology. Section 11.02. ASTM International. 100 Barr Harbor
Drive, West Conshohocken, PA 19428.
\11\ AOAC. 1995. Official Methods of Analysis of AOAC International, 16th Edition, Volume I, Chapter 17. Association of Official Analytical Chemists
International. 481 North Frederick Avenue, Suite 500, Gaithersburg, MD 20877-2417.
\12\ Recommended for enumeration of target organism in sewage sludge.
\13\ These tests are collectively known as defined enzyme substrate tests, where, for example, a substrate is used to detect the enzyme [beta]-
glucuronidase produced by E. coli.
\14\ USEPA. July 2006. Method 1680: Fecal Coliforms in Sewage Sludge (Biosolids) by Multiple-Tube Fermentation Using Lauryl-Tryptose Broth (LTB) and EC
Medium. US Environmental Protection Agency, Office of Water, Washington, DC EPA-821-R-06-012.
\15\ Samples shall be enumerated by the multiple-tube or multiple-well procedure. Using multiple-tube procedures, employ an appropriate tube and
dilution configuration of the sample as needed and report the Most Probable Number (MPN). Samples tested with Colilert[reg] may be enumerated with the
multiple-well procedures, Quanti-Tray[reg] Quanti-Tray[reg] 2000, and the MPN calculated from the table provided by the manufacturer.
\16\ Colilert-18[reg] is an optimized formulation of the Colilert[reg] for the determination of total coliforms and E. coli that provides results within
18 h of incubation at 35 [deg]C rather than the 24 h required for the Colilert[reg] test and is recommended for marine water samples.
\17\ Descriptions of the Colilert[reg], Colilert-18[reg], Quanti-Tray[reg], and Quanti-Tray[reg]/2000 may be obtained from IDEXX Laboratories, Inc., 1
IDEXX Drive, Westbrook, ME 04092.
\18\ A description of the mColiBlue24[reg] test, Total Coliforms and E. coli, is available from Hach Company, 100 Dayton Ave., Ames, IA 50010.
\19\ USEPA. July 2006. Method 1681: Fecal Coliforms in Sewage Sludge (Biosolids) by Multiple-Tube Fermentation using A-1 Medium. U.S. Environmental
Protection Agency, Office of Water, Washington, DC EPA-821-R-06-013.
\20\ Recommended for enumeration of target organism in wastewater effluent.
\21\ USEPA. July 2006. Method 1603: Escherichia coli (E. coli) in Water by Membrane Filtration Using Modified membrane-Thermotolerant Escherichia coli
Agar (modified mTEC). U.S. Environmental Protection Agency, Office of Water, Washington, DC EPA-821-R-06-011.
\22\ USEPA. July 2006. Method 1682: Salmonella in Sewage Sludge (Biosolids) by Modified Semisolid Rappaport-Vassiliadis (MSRV) Medium. U.S.
Environmental Protection Agency, Office of Water, Washington, DC EPA-821-R-06-014.
\23\ A description of the Enterolert[reg] test may be obtained from IDEXX Laboratories, Inc., 1 IDEXX Drive, Westbrook, ME 04092.
\24\ USEPA. July 2006. Method 1600: Enterococci in Water by Membrane Filtration Using membrane-Enterococcus Indoxyl-[beta]-D-Glucoside Agar (mEI). U.S.
Environmental Protection Agency, Office of Water, Washington, DC EPA-821-R-06-009.
\25\ USEPA. October 2002. Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms. Fifth Edition.
U.S. Environmental Protection Agency, Office of Water, Washington, DC EPA/821/R-02/012.
\26\ USEPA. October 2002. Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth
Edition, U.S. Environmental Protection Agency, Office of Water, Washington, DC EPA/821/R-02/013.
\27\ USEPA. October 2002. Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Marine and Estuarine Organisms.
Third Edition. U.S. Environmental Protection Agency, Office of Water, Washington, DC EPA/821/R-02/014.
Table IB--List of Approved Inorganic Test Procedures
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Reference (method number or page)
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Parameter Methodology \58\ Standard methods Standard methods Standard methods
EPA \35,\ \52\ (18th, 19th) (20th) online ASTM USGS/AOAC/other
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1. Acidity, as CaCO3, mg/L....... Electrometric ..................... 2310 B(4a)........... 2310 B(4a)........... 2310 B(4a)-97......... D1067-92, 02........ I-1020-85 \2\
endpoint or
phenolphthalein
endpoint.
[[Page 10]]
2. Alkalinity, as CaCO3, mg/L.... Electrometric or ..................... 2320 B............... 2320 B............... 2320 B-97............. D1067-92, 02........ 973.43 \3\, I-1030-
Colorimetric 85 \2\
titration to pH
4.5, manual, or
automatic........... 310.2 (Rev. 1974) \1\ ..................... ..................... ...................... .................... I-2030-85 \2\
3. Aluminum--Total,\4\ mg/L...... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 D............... ..................... 3111 D-99............. .................... I-3051-85 \2\
\36\.
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99.............
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-9750
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14\3\
(1994).
Direct Current ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Plasma (DCP) \36\.
Colorimetric ..................... 3500-Al D............ 3500-Al B............ 3500-Al B-01..........
(Eriochrome cyanine
R).
4. Ammonia (as N), mg/L.......... Manual, distillation 350.1, Rev. 2.0 4500-NH B3........... 4500-NH3 B........... 4500-NH3 B-97......... .................... 973.49 \3\
(at pH 9.5) \6\ (1993).
followed by:
Nesslerization...... ..................... 4500-NH3 C (18th ..................... ...................... D1426-98, 03 (A).... 973.49 \3\, I-3520-
only). 85 \2\
Titration........... ..................... 4500-NH3 C (19th) and 4500-NH3 C........... 4500-NH3 C-97.........
4500-NH3 E (18th).
Electrode........... ..................... 4500-NH3 D or E 4500-NH3 D or E...... 4500-NH3 D or E-97.... D1426-98, 03 (B)....
(19th) and 4500-NH3
F or G (18th).
[[Page 11]]
Automated phenate, 350.1 \60\, Rev. 2.0 4500-NH3 G (19th) and 4500-NH3 G........... 4500-NH3 G-97......... .................... I-4523-85 \2\
or. (1993). 4500-NH3 H (18th).
Automated electrode. ..................... ..................... ..................... ...................... .................... See footnote 7
Ion Chromatography.. ..................... ..................... ..................... ...................... D6919-03............
5. Antimony--Total, \4\ mg/L..... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99.............
\36\.
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99.............
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99.............
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
6. Arsenic--Total, \4\ mg/L...... Digestion \4\ 206.5 (Issued 1978)
followed by. \1\.
AA gaseous hydride.. ..................... 3114 B 4.d........... ..................... 3114 B 4.d-97......... D2972-97, 03 (B).... I-3062-85 \2\
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D2972-97, 03 (C).... I-4063-98 \49\
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99.............
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
Colorimetric (SDDC). ..................... 3500-As C............ 3500-As B............ 3500-As B-97.......... D2972-97, 03 (A).... I-3060-85
7. Barium--Total,\4\ mg/L........ Digestion \4\
followed by:
AA direct aspiration ..................... 3111 D............... ..................... 3111 D-99............. .................... I-3084-85 \2\
\36\.
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D4382-95, 02........
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99.............
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP \36\............ ..................... ..................... ..................... ...................... .................... See footnote \34\
8. Beryllium--Total,\4\ mg/L..... Digestion \4\
followed by:
[[Page 12]]
AA direct aspiration ..................... 3111 D............... ..................... 3111 D-99............. D3645-93 (88), 03 I-3095-85 \2\
(A).
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D3645-93 (88), 03
(B).
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP, or............. ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Colorimetric ..................... 3500-Be D............
(aluminon).
9. Biochemical oxygen demand Dissolved Oxygen ..................... 5210 B............... 5210 B............... 5210 B-01............. .................... 973.44,\3\ p.
(BOD5), mg/L. Depletion. 17.\9\, I-1578-78
\8\
10. Boron--Total,\37\ mg/L....... Colorimetric ..................... 4500-B B............. 4500-B B............. 4500-B B-00........... .................... I-3112-85 \2\
(curcumin).
ICP/AES, or......... 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B 99............. .................... I-4471-97 \50\
(1994).
DCP................. ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote 34
11. Bromide, mg/L................ Titrimetric......... ..................... ..................... ..................... ...................... D1246-95, 99 (C).... p. S44.\10\
.................... ..................... ..................... ..................... ...................... .................... I-1125-85 \2\
Ion Chromatography.. 300.0, Rev 2.1 (1993) 4110 B............... 4110 B............... 4110 B-00............. D4327-97, 03........ 993.30 \3\
and 300.1, Rev 1.0
(1997).
CIE/UV.............. ..................... ..................... ..................... ...................... .................... D6508, Rev. 2 \54\
12. Cadmium--Total,\4\ mg/L...... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B or C.......... ..................... 3111 B or C-99........ D3557-95, 02 (A or 974.27,\3\ p.
\36\. B). 37.\9\, I-3135-85
\2\ or I-3136-85
\2\
[[Page 13]]
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D3557-95, 02 (D).... I-4138-89 \51\
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-1472-85\2\ or I-
(1994). 4471-97 \50\
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP \36\............ ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Voltametry \11\, or. ..................... ..................... ..................... ...................... D3557-95, 02 (C)....
Colorimetric ..................... 3500-Cd D............
(Dithizone).
13. Calcium--Total,\4\ mg/L...... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99............. D511-93, 03(B)...... I-3152-85 \2\
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
DCP, or............. ..................... ..................... ..................... ...................... .................... See footnote \34\
Titrimetric (EDTA).. ..................... 3500-Ca D............ 3500-Ca B............ 3500-Ca B-97.......... D511-93, 03(A)......
Ion Chromatography.. ..................... ..................... ..................... ...................... D6919-03............
14. Carbonaceous biochemical Dissolved Oxygen ..................... 5210 B............... 5210 B............... 5210 B-01.............
oxygen demand (CBOD5), mg/L \12\. Depletion with
nitrification
inhibitor.
15. Chemical oxygen demand (COD), Titrimetric......... 410.3 (Rev. 1978) \1\ 5220 C............... 5220 C............... 5220 C-97............. D1252-95, 00 (A).... 973.46 \3\, p. 17
mg/L. \9\ I-3560-85 \2\
Spectrophotometric, 410.4, Rev. 2.0 5220 D............... 5220 D............... 5220 D-97............. D1252-95, 00 (B).... See footnotes
manual or automatic. (1993). \13,14\. I-3561-85
\2\
16. Chloride, mg/L............... Titrimetric: (silver ..................... 4500-Cl-B............ 4500-Cl-B............ 4500-Cl-B-97.......... D512-89(99) (B)..... I-1183-85 \2\
nitrate) or.
(Mercuric nitrate).. ..................... 4500-Cl-C............ 4500-Cl-C............ 4500-Cl-C-97.......... D512-89 (99) (A).... 973.51 \3\, I-1184-
85 \2\
Colorimetric: manual ..................... ..................... ..................... ...................... .................... I-1187-85 \2\
or.
Automated ..................... 4500-Cl-E............ 4500-Cl-E............ 4500-Cl-E-97.......... .................... I-2187-85 \2\
(Ferricyanide).
Potentiometric ..................... 4500-Cl-D............ 4500-Cl-D............ 4500-Cl-D-97..........
Titration.
Ion Selective ..................... ..................... ..................... ...................... D512-89(99)(C)......
Electrode.
[[Page 14]]
Ion Chromatography.. 300.0, Rev 2.1 (1993) 4110 B............... 4110 B............... 4110 B-00............. D4327-97, 03........ 993.30 \3\
and 300.1, Rev 1.0
(1997).
CIE/UV.............. ..................... ..................... ..................... ...................... .................... D6508, Rev. 2 \54\
17. Chlorine--Total residual, mg/ Amperometric direct, ..................... 4500-Cl D............ 4500-Cl D............ 4500-Cl D-00.......... D1253-86 (96), 03...
L; Titrimetric. or.
Amperometric direct ..................... 4500-Cl E............ 4500-Cl E............ 4500-Cl E-00..........
(low level).
Iodometric direct... ..................... 4500-Cl B............ 4500-Cl B............ 4500-Cl B-00..........
Back titration ether ..................... 4500-Cl C............ 4500-Cl C............ 4500-Cl C-00..........
end-point \15\ or.
DPD-FAS............. ..................... 4500-Cl F............ 4500-Cl F............ 4500-Cl F-00..........
Spectrophotometric, ..................... 4500-Cl G............ 4500-Cl G............ 4500-Cl G-00..........
DPD or.
Electrode........... ..................... ..................... ..................... ...................... .................... See footnote \16\
18. Chromium VI dissolved, mg/L.. 0.45-micron
Filtration followed
by:
AA chelation- ..................... 3111 C............... ..................... 3111 C-99............. .................... I-1232-85
extraction or.
Ion Chromatography.. 218.6, Rev. 3.3 3500-Cr E............ 3500-Cr C............ 3500-Cr C-01.......... D5257-97............ 993.23
(1994).
Colorimetric ..................... 3500-Cr D............ 3500-Cr B............ 3500-Cr B-01.......... D1687-92, 02 (A).... I-1230-85
(Diphenyl-
carbazide).
19. Chromium--Total,\4\ mg/L..... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99............. D1687-92, 02 (B).... 974.27 \3\, I-3236-
\36\. 85 \2\
AA chelation- ..................... 3111 C............... ..................... 3111 C-99.............
extraction.
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D1687-92, 02 (C).... I-3233-93 \46\
STGFAA.............. 200.9, Rev. 2.2
(1994).
[[Page 15]]
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99.............
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP,\36\ or......... ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Colorimetric ..................... 3500-Cr D............ 3500-Cr B............ 3500-Cr B-01..........
(Diphenyl-
carbazide).
20. Cobalt--Total,\4\ mg/L....... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B or C.......... ..................... 3111 B or C-99........ D3558-94, 03 (A or p. 37 \9\, I-3239-85
B). \2\
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D3558-94, 03 (C).... I-4243-89 \51\
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP................. ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
21. Color, platinum cobalt units Colorimetric (ADMI), ..................... 2120 E............... 2120 E............... ...................... .................... See footnote \18\
or dominant wavelength, hue, or.
luminance purity.
(Platinum cobalt), ..................... 2120 B............... 2120 B............... 2120 B-01............. .................... I-1250-85 \2\
or.
Spectrophotometric.. ..................... 2120 C............... 2120 C...............
22. Copper--Total,\4\ mg/L....... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B or C.......... ..................... 3111 B or C-99........ D1688-95, 02 (A or 974.27 \3\ p. 37 \9\
\36\. B). I-3270-85 \2\ or I-
3271-85 \2\
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D1688-95, 02 (C).... I-4274-89 \51\
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP \36\ or......... ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Colorimetric ..................... 3500-Cu D............ 3500-Cu B............ 3500-Cu B-99..........
(Neocuproine) or.
(Bicinchoninate).... ..................... 3500-Cu E............ 3500-Cu C............ 3500-Cu C-99.......... .................... See footnote \19\
[[Page 16]]
23. Cyanide--Total, mg/L......... Automated ..................... ..................... ..................... ...................... .................... Kelada-01 \55\
Distillation and
Colorimetry, or.
Manual distillation 335.4, Rev. 1.0 4500-CN C............ 4500-CN C............ ...................... D2036-98(A)......... 10-204-00-1-X \56\
with MgCl2 followed (1993) \57\.
by:
Titrimetric or...... ..................... 4500-CN D............ 4500-CN D............ 4500-CN D-99.......... .................... p. 22 \9\
Spectrophotometric, ..................... 4500-CN E............ 4500-CN E............ 4500-CN E-99.......... D2036-98(A)......... I-3300-85
manual or.
Automated \20\ or... 335.4, Rev. 1.0 ..................... ..................... ...................... .................... 10-204-00-1-X \56\,
(1993) \57\. I-4302-85 \2\
Ion Selective ..................... 4500-CN F............ 4500-CN F............ 4500-CN F-99.......... D2036-98(A).........
Electrode.
24. Available Cyanide, mg/L...... Cyanide Amenable to ..................... 4500-CN G............ 4500-CN G............ 4500-CN G-99.......... D2036-98(B).........
Chlorination
(CATC); Manual
distillation with
MgCl2 followed by
Titrimetric or
Spectrophotometric.
Flow injection and ..................... ..................... ..................... ...................... D6888-04............ OIA-1677 \44\
ligand exchange,
followed by
amperometry \61\.
Automated ..................... ..................... ..................... ...................... .................... Kelada-01 \55\
Distillation and
Colorimetry.
25. Fluoride--Total, mg/L........ Manual ..................... 4500-F B............. 4500-F B............. 4500-F B-97...........
distillation\6\
followed by:
Electrode, manual or ..................... 4500-F B............. 4500-F B............. 4500-F C-97........... D1179-93, 99 (B)....
Automated........... ..................... ..................... ..................... ...................... .................... I-4327-85 \2\
Colorimetric, ..................... 4500-F D............. 4500-F D............. 4500-F D-97........... D1179-93, 99 (A)....
(SPADNS) or.
[[Page 17]]
Automated complexone ..................... 4500-F E............. 4500-F E............. 4500-F E-97...........
Ion Chromatography.. 300.0, Rev 2.1 (1993) 4110 B............... 4110 B............... 4110 B-00............. D4327-97,03......... 993.30 \3\
and 300.1, Rev 1.0
(1997).
CIE/UV.............. ..................... ..................... ..................... ...................... .................... D6508, Rev. 2 \54\
26. Gold--Total,\4\ mg/L......... Digestion \4\
followed by:
AA direct ..................... 3111 B............... ..................... 3111 B-99.............
aspiration, or.
AA furnace, or...... 231.2 (Rev. 1978) \1\
DCP................. ..................... ..................... ..................... ...................... .................... See footnote \34\
27. Hardness--Total, as CaCO3, mg/ Automated 130.1 (Issued 1971)
L. colorimetric,. \1\.
Titrimetric (EDTA) ..................... 2340 B or C.......... 2340 B or C.......... 2340 B or C-97........ D1126-86(92), 02.... 973.5 2B \3\, I-1338-
or. 85\2\
Ca plus Mg as their
carbonates, by
inductively coupled
plasma or AA direct
aspiration. (See
Parameters 13 and
33)..
28. Hydrogen ion (pH), pH units.. Electrometric ..................... 4500-H+ B............ 4500-H+ B............ 4500-H+ B-00.......... D1293-84 (90), 99 (A 973.41.\3\, I-1586-
measurement or. or B). 85 \2\
Automated electrode. 150.2 (Dec. 1982) \1\ ..................... ..................... ...................... .................... See footnote\21\, I-
2587-85\2\
29. Iridium--Total,\4\ mg/L...... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99.............
or.
AA furnace.......... 235.2 (Issued 1978)
\1\.
30. Iron--Total,\4\ mg/L......... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B or C.......... ..................... 3111 B or C-99........ D1068-96, 03 (A or 974.27 \3\, I-3381-
\36\. B). 85 \2\
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D1068-96, 03 (C)....
STGFAA.............. 200.9, Rev. 2.2
(1994).
[[Page 18]]
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
DCP \36\ or......... ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Colorimetric ..................... 3500-Fe D............ 3500-Fe B............ 3500-Fe B-97.......... D1068-96, 03 (D).... See footnote \22\
(Phenanthroline).
31. Kjeldahl Nitrogen \5\--Total, Digestion and ..................... 4500-Norg B or C and 4500-Norg B or C and 4500-Norg B or C-97 D3590-89, 02 (A)....
(as N), mg/L. distillation 4500-NH3 B. 4500-NH3 B. and 4500-NH3 B-97.
followed by: \20\
Titration or........ ..................... 4500-NH3 C (19th) and 4500-NH3 C........... 4500-NH3 C-97......... D3590-89, 02 (A).... 973.48 \3\
4500-NH 3 E (18th).
Nesslerization or... ..................... 4500-NH3 C (18th ..................... ...................... D3590-89, 02 (A)....
Only).
Electrode........... ..................... 4500-NH3 F or G 4500-NH3 D or E...... 4500-NH3 D or E-97....
(18th) and 4500-NH3
D or E (19th).
Automated phenate 351.1 (Rev. 1978) \1\ ..................... ..................... ...................... .................... I-4551-78 \8\
colorimetric.
Semi-automated block 351.2, Rev. 2.0 ..................... ..................... ...................... D3590-89, 02 (B).... I-4515-91 \45\
digestor (1993).
colorimetric.
Manual or block ..................... ..................... ..................... ...................... D3590-89, 02 (A)....
digestor
potentiometric.
Block digester, ..................... ..................... ..................... ...................... .................... See footnote \39\
followed by Auto
distillation and
Titration, or.
Nesslerization, or.. ..................... ..................... ..................... ...................... .................... See footnote \40\
Flow injection gas ..................... ..................... ..................... ...................... .................... See footnote \41\
diffusion.
32. Lead--Total,\4\ mg/L......... Digestion \4\
followed by:
[[Page 19]]
AA direct aspiration ..................... 3111 B or C.......... ..................... 3111 B or C-99........ D3559-96, 03 (A or 974.27 \3\, I-3399-
\36\. B). 85 \2\
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D3559-96, 03 (D).... I-4403-89 \51\
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP \36\............ ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Voltametry \11\ or.. ..................... ..................... ..................... ...................... D3559-96, 03 (C)....
Colorimetric ..................... 3500-Pb D............ 3500-Pb B............ 3500-Pb B-97..........
(Dithizone).
33. Magnesium--Total,\4\ mg/L.... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99............. D511-93, 03(B)...... 974.27 \3\, I-3447-
85 \2\
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
DCP or.............. ..................... ..................... ..................... ...................... .................... See footnote \34\
Gravimetric......... ..................... 3500-Mg D............
Ion Chromatography.. ..................... ..................... ..................... ...................... D6919-03............
34. Manganese--Total,\4\ mg/L.... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99............. D858-95, 02 (A or B) 974.27 \3\, I-3454-
\36\. 85 \2\
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D858-95, 02 (C).....
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP36, or........... ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Colorimetric ..................... 3500--Mn D........... 3500-Mn B............ 3500-Mn B-99.......... .................... 920.203 \3\
(Persulfate), or.
(Periodate)......... ..................... ..................... ..................... ...................... .................... See footnote \23\
35. Mercury--Total \4\, mg/L..... Cold vapor, manual 245.1, Rev. 3.0 3112 B............... ..................... 3112 B-99............. D3223-97, 02........ 977.22 \3\, I-3462-
or. (1994). 85\2\
Automated........... 245.2 (Issued 1974)..
[[Page 20]]
Cold vapor atomic 245.7 Rev. 2.0 (2005)
fluorescence \59\.
spectrometry
(CVAFS).
Purge and Trap CVAFS 1631E \43\...........
36. Molybdenum--Total \4\, mg/L.. Digestion \4\
followed by:
AA direct aspiration ..................... 3111 D............... ..................... 3111 D-99............. .................... I-3490-85 \2\
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. .................... I-3492-96 \47\
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP................. ..................... ..................... ..................... ...................... .................... See footnote \34\
37. Nickel--Total,\4\ mg/L....... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B or C.......... ..................... 3111 B or C-99........ D1886-90, 94 (98) (A I-3499-85 \2\
\36\. or B).
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D1886-90, 94 (98) I-4503-89 \51\
(C).
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP \36\, or........ ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Colorimetric ..................... 3500-Ni D (17th
(heptoxime). Edition).
38. Nitrate (as N), mg/L......... Ion Chromatography.. 300.0, Rev 2.1 (1993) 4110 B............... 4110 B............... 4110 B-00............. D4327-97, 03........ 993.30 \3\
and 300.1, Rev 1.0
(1997).
CIE/UV.............. ..................... ..................... ..................... ...................... .................... D6508, Rev. 2 \54\
[[Page 21]]
Ion Selective ..................... 4500-NO3 D.......... 4500-NO3 D.......... 4500-NO3 D-00........
Electrode.
Colorimetric 352.1 \1\............ ..................... ..................... ...................... .................... 973.50 \3\, 419D
(Brucine sulfate), \1,\ \7\, p. 28 \9\
or.
Nitrate-nitrite N
minus Nitrite N
(See parameters 39
and 40)..
39. Nitrate-nitrite (as N), mg/L. Cadmium reduction, ..................... 4500-NO3 E........... 4500-NO3 E........... 4500-NO3 E-00......... D3867-99(B).........
manual or.
Automated, or....... 353.2, Rev. 2.0 4500-NO3 F........... 4500-NO3 F........... 4500-NO3 F-00......... D3867-99(A)......... I-4545-85 \2\
(1993).
Automated hydrazine. ..................... 4500-NO3 H........... 4500-NO3 H........... 4500-NO3 H-00.........
Ion Chromatography.. 300.0, Rev 2.1 (1993) 4110 B............... 4110 B............... 4110 B-00............. D4327-97............ 993.30 \3\
and 300.1, Rev 1.0
(1997).
CIE/UV.............. ..................... ..................... ..................... ...................... .................... D6508, Rev. 2 \54\
40. Nitrite (as N), mg/L......... Spectrophotometric: ..................... 4500-NO2 B........... 4500-NO2 B........... 4500-NO2 B-00......... .................... See footnote \25\
Manual or.
Automated ..................... ..................... ..................... ...................... .................... I-4540-85 \2\
(Diazotization).
Automated (*bypass 353.2, Rev. 2.0 4500-NO3 F........... 4500-NO3 F........... 4500-NO3 F-00......... D3867-99(A)......... I-4545-85 \2\
cadmium reduction). (1993).
Manual (*bypass ..................... 4500-NO3 E........... 4500-NO3 E........... 4500-NO3 E-00......... D3867-99(B).........
cadmium reduction).
Ion Chromatography.. 300.0, Rev 2.1 (1993) 4110 B............... 4110 B............... 4110 B-00............. D4327-97, 03........ 993.30 \3\
and 300.1, Rev 1.0
(1997).
CIE/UV.............. ..................... ..................... ..................... ...................... .................... D6508, Rev.2 \54\
41. Oil and grease--Total Hexane extractable 1664A \42\........... ..................... 5520 B \38\.......... 5520 B-01 \38\........
recoverable, mg/L. material (HEM): n-
Hexane extraction
and gravimetry.
Silica gel treated 1664A \42\...........
HEM (SGT-HEM):
Silica gel
treatment and
gravimetry..
[[Page 22]]
42. Organic carbon--Total (TOC), Combustion or ..................... 5310 B, C, or D...... 5310 B, C, or D...... 5310 B, C, or D-00.... D2579-93 (A or B)... 973.47,\3\ p. 14
mg/L. oxidation. \24\
43. Organic nitrogen (as N), mg/L Total Kjeldahl N
(Parameter 31)
minus ammonia N
(Parameter 4).
44. Orthophosphate (as P), mg/L.. Ascorbic acid
method:.
Automated, or....... 365.1, Rev. 2.0 4500-P F............. 4500-P F............. ...................... .................... 973.56 \3\, I-4601-
(1993). 85 \2\
Manual single ..................... 4500-P E............. 4500-P E............. ...................... D515-88(A).......... 973.55 \3\
reagent.
Manual two reagent.. 365.3 (Issued
1978)\1\.
Ion Chromatography.. 300.0, Rev 2.1 (1993) 4110 B............... 4110 B............... 4110 B-00............. D4327-97, 03........ 993.30 \3\
and 300.1, Rev 1.0
(1997).
CIE/UV.............. ..................... ..................... ..................... ...................... .................... D6508, Rev. 2 \54\
45. Osmium--Total \4\, mg/L...... Digestion \4\
followed by:
AA direct ..................... 3111 D............... ..................... 3111 D-99.............
aspiration, or.
AA furnace.......... 252.2 (Issued 1978)
\1\.
46. Oxygen, dissolved, mg/L...... Winkler (Azide ..................... 4500-O C............. 4500-O C............. 4500-O C-01........... D888-92, 03 (A)..... 973.4 5B \3\, I-1575-
modification), or. 78 \8\
Electrode........... ..................... 4500-O G............. 4500-O G............. 4500-O G-01........... D888-92, 03 (B)..... I-1576-78 \8\
47. Palladium--Total,\4\ mg/L.... Digestion \4\
followed by:
AA direct ..................... 3111 B............... ..................... 3111 B-99............. .................... p. S27 \10\
aspiration, or.
AA furnace.......... 253.2 \1\ (Issued ..................... ..................... ...................... .................... p. S28 \10\
1978).
[[Page 23]]
DCP................. ..................... ..................... ..................... ...................... .................... See footnote \34\
48. Phenols, mg/L................ Manual distillation 420.1 \1\ (Rev. 1978) ..................... ..................... ...................... .................... See footnote \27\
\26\ Followed by:
Colorimetric (4AAP) 420.1 \1\ (Rev. 1978) ..................... ..................... ...................... .................... See footnote \27\
manual, or.
Automated........... 420.4 Rev. 1.0 (1993)
49. Phosphorus (elemental), mg/L. Gas-liquid ..................... ..................... ..................... ...................... .................... See footnote \28\
chromatography.
50. Phosphorus--Total, mg/L...... Persulfate digestion ..................... 4500-P B.5........... 4500-P B.5........... ...................... .................... 973.55 \3\
followed by: \20\
Manual or........... 365.3 \1\ (Issued 4500-P E............. 4500-P E............. ...................... D515-88(A)..........
1978).
Automated ascorbic 365.1 Rev. 2.0 (1993) 4500-P F............. 4500-P F............. ...................... .................... 973.56 \3\, I-4600-
acid reduction. 85 \2\
Semi-automated block 365.4 \1\ (Issued ..................... ..................... ...................... D515-88(B).......... I-4610-91 \48\
digestor. 1974).
51. Platinum--Total,\4\ mg/L..... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99.............
AA furnace.......... 255.2 \1\............
DCP................. ..................... ..................... ..................... ...................... .................... See footnote \34\
52. Potassium--Total,\4\ mg/L.... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99............. .................... 973.53 \3\, I-3630-
85 \2\
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99.............
(1994).
Flame photometric, ..................... 3500-K D............. 3500-K B............. 3500-K B-97...........
or.
Colorimetric........ ..................... ..................... ..................... ...................... .................... 317 B \17\
Ion Chromatography.. ..................... ..................... ..................... ...................... D6919-03............
53. Residue--Total, mg/L......... Gravimetric, 103- ..................... 2540 B............... 2540 B............... 2540 B-97............. .................... I-3750-85 \2\
105[deg].
54. Residue--filterable, mg/L.... Gravimetric, ..................... 2540 C............... 2540 C............... 2540 C-97............. .................... I-1750-85 \2\
180[deg].
55. Residue--non-filterable Gravimetric, 103-105 ..................... 2540 D............... 2540 D............... 2540 D-97............. .................... I-3765-85 \2\
(TSS), mg/L. [deg]C post washing
of residue.
56. Residue--settleable, mg/L.... Volumetric, (Imhoff ..................... 2540 F............... 2540 F............... 2540 F-97.............
cone), or
gravimetric.
57. Residue--Volatile, mg/L...... Gravimetric, 550 160.4 \1\............ ..................... ..................... ...................... .................... I-3753-85 \2\
[deg]C.
[[Page 24]]
58. Rhodium--Total,\4\ mg/L...... Digestion \4\
followed by:
AA direct ..................... 3111 B............... ..................... 3111 B-99.............
aspiration, or.
AA furnace.......... 265.2 \1\............
59. Ruthenium--Total,\4\ mg/L.... Digestion \4\
followed by:
AA direct ..................... 3111 B............... ..................... 3111 B-99.............
aspiration, or.
AA furnace.......... 267.2 \1\............
60. Selenium--Total,\4\ mg/L..... Digestion \4\
followed by:
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. D3859-98, 03 (B).... I-4668-98 \49\
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99.............
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
AA gaseous hydride.. ..................... 3114 B............... ..................... 3114 B-97............. D3859-98, 03 (A).... I-3667-85 \2\
61. Silica--Dissolved,\37\ mg/L.. 0.45 micron
filtration followed
by:
Colorimetric, Manual ..................... 4500-Si D............ 4500-SiO2 C.......... 4500-SiO2C-97......... D859-94, 00......... I-1700-85 \2\
or.
Automated ..................... ..................... ..................... ...................... .................... I-2700-85 \2\
(Molybdosilicate),
or.
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
62. Silver--Total,4, 31 mg/L..... Digestion 4, 29
followed by:
AA direct aspiration ..................... 3111 B or C.......... ..................... 3111 B or C-99........ .................... 974.27 \3\, p. 37
\9\, I-3720-85 \2\
[[Page 25]]
AA furnace.......... ..................... 3113 B............... ..................... 3113 B-99............. .................... I-4724-89 \51\
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP................. ..................... ..................... ..................... ...................... .................... See footnote \34\
63. Sodium--Total,\4\ mg/L....... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99............. .................... 973.54 \3\, I-3735-
85 \2\
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
DCP, or............. ..................... ..................... ..................... ...................... .................... See footnote \34\
Flame photometric... ..................... 3500-Na D............ 3500-Na B............ 3500-Na B-97..........
Ion Chromatography.. ..................... ..................... ..................... ...................... D 6919-03...........
64. Specific conductance, Wheatstone bridge... 120.1 \1\ (Rev. 1982) 2510 B............... 2510 B............... 2510 B-97............. D1125-95 (99) (A)... 973.40 \3\, I-2781-
micromhos/cm at 25 [deg]C. 85 \2\
65. Sulfate (as SO4), mg/L....... Automated 375.2, Rev. 2.0
colorimetric. (1993).
Gravimetric......... ..................... 4500-SO4 \2\ C or D.. 4500-SO4 \2\ C or D.. ...................... .................... 925.54 \3\
Turbidimetric....... ..................... ..................... ..................... ...................... D516-90, 02......... 426C \3\0
Ion Chromatography.. 300.0, Rev 2.1 (1993) 4110 B............... 4110 B............... 4110 B-00............. D4327-97, 03........ 993.30 \3\
and 300.1, Rev 1.0
(1997).
CIE/UV.............. ..................... ..................... ..................... ...................... .................... D6508, Rev. 2 \54\
66. Sulfide (as S), mg/L......... Titrimetric ..................... 4500-S \2\ F (19th) 4500-S \2\ F......... 4500-S \2\ F-00....... .................... I-3840-85 \2\
(iodine), or. 4500-S \2\ E (18th).
Colorimetric ..................... 4500-S \2\ D......... 4500-S \2\ D......... 4500-S \2\ D-00.......
(methylene blue).
Ion Selective ..................... 4500-S \2\ G......... 4500-S \2\ G......... 4500-S \2\ G-00....... D4658-03............
Electrode.
67. Sulfite (as SO3), mg/L....... Titrimetric (iodine- ..................... 4500-SO3 \2\ B....... 4500-SO3 \2\ B....... 4500-SO3 \2\ B-00.....
iodate).
68. Surfactants, mg/L............ Colorimetric ..................... 5540 C............... 5540 C............... 5540 C-00............. D2330-88, 02........
(methylene blue).
69. Temperature, [deg]C.......... Thermometric........ ..................... 2550 B............... 2550 B............... 2550 B-00............. .................... See footnote \32\
70. Thallium--Total, \4\ mg/L.... Digestion \4\
followed by:
[[Page 26]]
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99.............
AA furnace.......... 279.2 \1\ (Issued
1978).
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99.............
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
71. Tin--Total,\4\ mg/L.......... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B............... ..................... 3111 B-99............. .................... I-3850-78 \8\
AA furnace, or...... ..................... 3113 B............... ..................... 3113 B-99.............
STGFAA.............. 200.9, Rev. 2.2
(1994).
ICP/AES............. 200.7, Rev. 4.4
(1994).
72. Titanium--Total,\4\ mg/L..... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 D............... ..................... 3111 D-99.............
AA furnace.......... 283.2 \1\ (Issued
1978).
DCP................. ..................... ..................... ..................... ...................... .................... See footnote \34\
73. Turbidity, NTU \53\.......... Nephelometric....... 180.1, Rev. 2.0 2130 B............... 2130 B............... 2130 B-01............. D1889-94, 00........ I-3860-85 \2\
(1993).
74. Vanadium--Total,\4\ mg/L..... Digestion \4\
followed by:
AA direct aspiration ..................... 3111 D............... ..................... 3111 D-99.............
AA furnace.......... ..................... ..................... ..................... ...................... D3373-93, 03........
ICP/AES............. 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99............. .................... I-4471-97 \50\
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP, or............. ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Colorimetric (Gallic ..................... 3500-V D............. 3500-V B............. 3500-V B-97...........
Acid).
[[Page 27]]
75. Zinc -Total \4\, mg/L........ Digestion \4\
followed by:
AA direct aspiration ..................... 3111 B or C.......... ..................... 3111 B or C-99........ D1691-95, 02 (A or 974.27 \3\, p. 37
\36\. B). \9\, I-3900-85 \2\
AA furnace.......... 289.2 \1\ (Issued
1978).
ICP/AES \36\........ 200.7, Rev. 4.4 3120 B............... 3120 B............... 3120 B-99 \59\........ .................... I-4471-97 \50\
(1994).
ICP/MS.............. 200.8, Rev. 5.4 ..................... ..................... ...................... D5673-03............ 993.14 \3\
(1994).
DCP,\36\ or......... ..................... ..................... ..................... ...................... D4190-94, 99........ See footnote \34\
Colorimetric ..................... 3500-Zn E............
(Dithizone) or.
(Zincon)............ ..................... 3500-Zn F............ 3500-Zn B............ 3500-Zn B-97.......... .................... See footnote \33\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Table 1B Notes:
\1\ ``Methods for Chemical Analysis of Water and Wastes,'' Environmental Protection Agency, Environmental Monitoring Systems Laboratory-Cincinnati (EMSL-CI), EPA-600/4-79-020 (NTIS PB 84-
128677), Revised March 1983 and 1979 where applicable.
\2\ Fishman, M. J., et al. ``Methods for Analysis of Inorganic Substances in Water and Fluvial Sediments,'' U.S. Department of the Interior, Techniques of Water-Resource Investigations of the
U.S. Geological Survey, Denver, CO, Revised 1989, unless otherwise stated.
\3\ ``Official Methods of Analysis of the Association of Official Analytical Chemists,'' Methods Manual, Sixteenth Edition, 4th Revision, 1998.
\4\ For the determination of total metals (which are equivalent to total recoverable metals) the sample is not filtered before processing. A digestion procedure is required to solubilize
analytes in suspended material and to break down organic-metal complexes (to convert the analyte to a detectable form for colorimetric analysis). For non-platform graphite furnace atomic
absorption determinations a digestion using nitric acid (as specified in Section 4.1.3 of Methods for the Chemical Analysis of Water and Wastes) is required prior to analysis. The procedure
used should subject the sample to gentle, acid refluxing and at no time should the sample be taken to dryness. For direct aspiration flame atomic absorption determinations (FLAA) a
combination acid (nitric and hydrochloric acids) digestion is preferred prior to analysis. The approved total recoverable digestion is described as Method 200.2 in Supplement I of ``Methods
for the Determination of Metals in Environmental Samples'' EPA/600R-94/111, May, 1994, and is reproduced in EPA Methods 200.7, 200.8, and 200.9 from the same Supplement. However, when using
the gaseous hydride technique or for the determination of certain elements such as antimony, arsenic, selenium, silver, and tin by non-EPA graphite furnace atomic absorption methods, mercury
by cold vapor atomic absorption, the noble metals and titanium by FLAA, a specific or modified sample digestion procedure may be required and in all cases the referenced method write-up
should be consulted for specific instruction and/or cautions. For analyses using inductively coupled plasma-atomic emission spectrometry (ICP-AES), the direct current plasma (DCP) technique
or the EPA spectrochemical techniques (platform furnace AA, ICP-AES, and ICP-MS) use EPA Method 200.2 or an approved alternate procedure (e.g., CEM microwave digestion, which may be used
with certain analytes as indicated in Table IB); the total recoverable digestion procedures in EPA Methods 200.7, 200.8, and 200.9 may be used for those respective methods. Regardless of the
digestion procedure, the results of the analysis after digestion procedure are reported as ``total'' metals.
\5\ Copper sulfate may be used in place of mercuric sulfate.
\6\ Manual distillation is not required if comparability data on representative effluent samples are on file to show that this preliminary distillation step is not necessary: however, manual
distillation will be required to resolve any controversies.
\7\ Ammonia, Automated Electrode Method, Industrial Method Number 379-75 WE, dated February 19, 1976, Bran & Luebbe (Technicon) Auto Analyzer II, Bran & Luebbe Analyzing Technologies, Inc.,
Elmsford, NY 10523.
\8\ The approved method is that cited in ``Methods for Determination of Inorganic Substances in Water and Fluvial Sediments'', USGS TWRI, Book 5, Chapter A1 (1979).
\9\ American National Standard on Photographic Processing Effluents, April 2, 1975. Available from ANSI, 25 West 43rd st., New York, NY 10036.
\10\ ``Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency,'' Supplement to the Fifteenth Edition of Standard Methods for the Examination of
Water and Wastewater (1981).
\11\ The use of normal and differential pulse voltage ramps to increase sensitivity and resolution is acceptable.
[[Page 28]]
\12\ Carbonaceous biochemical oxygen demand (CBOD5) must not be confused with the traditional BOD5 test method which measures ``total BOD.'' The addition of the nitrification inhibitor is not
a procedural option, but must be included to report the CBOD5 parameter. A discharger whose permit requires reporting the traditional BOD5 may not use a nitrification inhibitor in the
procedure for reporting the results. Only when a discharger's permit specifically states CBOD5 is required can the permittee report data using a nitrification inhibitor.
\13\ OIC Chemical Oxygen Demand Method, Oceanography International Corporation, 1978, 512 West Loop, P.O. Box 2980, College Station, TX 77840.
\14\ Chemical Oxygen Demand, Method 8000, Hach Handbook of Water Analysis, 1979, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\15\ The back titration method will be used to resolve controversy.
\16\ Orion Research Instruction Manual, Residual Chlorine Electrode Model 97-70, 1977, Orion Research Incorporated, 840 Memorial Drive, Cambridge, MA 02138. The calibration graph for the Orion
residual chlorine method must be derived using a reagent blank and three standard solutions, containing 0.2, 1.0, and 5.0 mL 0.00281 N potassium iodate/100 mL solution, respectively.
\17\ The approved method is that cited in Standard Methods for the Examination of Water and Wastewater, 14th Edition, 1976.
\18\ National Council of the Paper Industry for Air and Stream Improvement, Inc., Technical Bulletin 253, December 1971.
\19\ Copper, Biocinchoinate Method, Method 8506, Hach Handbook of Water Analysis, 1979, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\20\ When using a method with block digestion, this treatment is not required.
\21\ Hydrogen ion (pH) Automated Electrode Method, Industrial Method Number 378-75WA, October 1976, Bran & Luebbe (Technicon) Autoanalyzer II. Bran & Luebbe Analyzing Technologies, Inc.,
Elmsford, NY 10523.
\22\ Iron, 1,10-Phenanthroline Method, Method 8008, 1980, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\23\ Manganese, Periodate Oxidation Method, Method 8034, Hach Handbook of Wastewater Analysis, 1979, pages 2-113 and 2-117, Hach Chemical Company, Loveland, CO 80537.
\24\ Wershaw, R. L.,et al., ``Methods for Analysis of Organic Substances in Water,'' Techniques of Water-Resources Investigation of the U.S. Geological Survey, Book 5, Chapter A3, (1972
Revised 1987) p. 14.
\25\ Nitrogen, Nitrite, Method 8507, Hach Chemical Company, P.O. Box 389, Loveland, CO 80537.
\26\ Just prior to distillation, adjust the sulfuric-acid-preserved sample to pH 4 with 1 + 9 NaOH.
\27\ The approved method is cited in Standard Methods for the Examination of Water and Wastewater, 14th Edition. The colorimetric reaction is conducted at a pH of 10.00.2. The approved methods are given on pp 576-81 of the 14th Edition: Method 510A for distillation, Method 510B for the manual colorimetric procedure, or Method 510C for the manual
spectrometric procedure.
\28\ R.F. Addison and R. G. Ackman, ``Direct Determination of Elemental Phosphorus by Gas-Liquid Chromatography,'' Journal of Chromatography, Vol. 47, No.3, pp. 421-426, 1970.
\29\ Approved methods for the analysis of silver in industrial wastewaters at concentrations of 1 mg/L and above are inadequate where silver exists as an inorganic halide. Silver halides such
as the bromide and chloride are relatively insoluble in reagents such as nitric acid but are readily soluble in an aqueous buffer of sodium thiosulfate and sodium hydroxide to pH of 12.
Therefore, for levels of silver above 1 mg/L, 20 mL of sample should be diluted to 100 mL by adding 40 mL each of 2 M Na2S2O3 and NaOH. Standards should be prepared in the same manner. For
levels of silver below 1 mg/L the approved method is satisfactory.
\30\ The approved method is that cited in Standard Methods for the Examination of Water and Wastewater, 15th Edition.
\31\ For samples known or suspected to contain high levels of silver (e.g., in excess of 4 mg/L), cyanogen iodide should be used to keep the silver in solution for analysis. Prepare a cyanogen
iodide solution by adding 4.0 mL of concentrated NH4OH, 6.5 g of KCN, and 5.0 mL of a 1.0 N solution of I2 to 50 mL of reagent water in a volumetric flask and dilute to 100.0 mL. After
digestion of the sample, adjust the pH of the digestate to >7 to prevent the formation of HCN under acidic conditions. Add 1 mL of the cyanogen iodide solution to the sample digestate and
adjust the volume to 100 mL with reagent water (NOT acid). If cyanogen iodide is added to sample digestates, then silver standards must be prepared that contain cyanogen iodide as well.
Prepare working standards by diluting a small volume of a silver stock solution with water and adjusting the pH>7 with NH4OH. Add 1 mL of the cyanogen iodide solution and let stand 1 hour.
Transfer to a 100-mL volumetric flask and dilute to volume with water.
\32\ Stevens, H.H., Ficke, J. F., and Smoot, G. F., ``Water Temperature--Influential Factors, Field Measurement and Data Presentation,'' Techniques of Water-Resources Investigations of the
U.S. Geological Survey, Book 1, Chapter D1, 1975.
\33\ Zinc, Zincon Method, Method 8009, Hach Handbook of Water Analysis, 1979, pages 2-231 and 2-333, Hach Chemical Company, Loveland, CO 80537.
\34\ ``Direct Current Plasma (DCP) Optical Emission Spectrometric Method for Trace Elemental Analysis of Water and Wastes, Method AES0029,'' 1986--Revised 1991, Thermo Jarrell Ash Corporation,
27 Forge Parkway, Franklin, MA 02038
\35\ Precision and recovery statements for the atomic absorption direct aspiration and graphite furnace methods, and for the spectrophotometric SDDC method for arsenic are provided in Appendix
D of this part titled, ``Precision and Recovery Statements for Methods for Measuring Metals.''
\36\ Microwave-assisted digestion may be employed for this metal, when analyzed by this methodology. ``Closed Vessel Microwave Digestion of Wastewater Samples for Determination of Metals'',
CEM Corporation, P.O. Box 200, Matthews, NC 28106-0200, April 16, 1992. Available from the CEM Corporation.
\37\ When determining boron and silica, only plastic, PTFE, or quartz laboratory ware may be used from start until completion of analysis.
[[Page 29]]
\38\ Only use n-hexane extraction solvent when determining Oil and Grease parameters--Hexane Extractable Material (HEM), or Silica Gel Treated HEM (analogous to EPA Method 1664A). Use of other
extraction solvents (e.g., those in the 18th and 19th editions) is prohibited.
\39\ Nitrogen, Total Kjeldahl, Method PAI-DK01 (Block Digestion, Steam Distillation, Titrimetric Detection), revised 12/22/94, OI Analytical/ALPKEM, P.O. Box 9010, College Station, TX 77842.
\40\ Nitrogen, Total Kjeldahl, Method PAI-DK02 (Block Digestion, Steam Distillation, Colorimetric Detection), revised 12/22/94, OI Analytical/ALPKEM, P.O. Box 9010, College Station, TX 77842.
\41\ Nitrogen, Total Kjeldahl, Method PAI-DK03 (Block Digestion, Automated FIA Gas Diffusion), revised 12/22/94, OI Analytical/ALPKEM, P.O. Box 9010, College Station, TX 77842.
\42\ Method 1664, Revision A ``n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and
Gravimetry'' EPA-821-R-98-002, February 1999. Available at NTIS, PB-121949, U.S. Department of Commerce, 5285 Port Royal, Springfield, VA 22161.
\43\ USEPA. 2001. Method 1631, Revision E, ``Mercury in Water by Oxidation, Purge and Trap, and Cold Vapor Atomic Fluorescence Spectrometry'' September 2002, Office of Water, U.S.
Environmental Protection Agency (EPA-821-R-02-024). The application of clean techniques described in EPA's draft Method 1669: Sampling Ambient Water for Trace Metals at EPA Water Quality
Criteria Levels (EPA-821-R-96-011) are recommended to preclude contamination at low-level, trace metal determinations.
\44\ Available Cyanide, Method OIA-1677, ``Available Cyanide by Flow Injection, Ligand Exchange, and Amperometry,'' ALPKEM, A Division of OI Analytical, P.O. Box 9010, College Station, TX
77842-9010.
\45\ ``Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Ammonia Plus Organic Nitrogen by a Kjeldahl Digestion Method,'' Open File Report
(OFR) 00-170.
\46\ ``Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Chromium in Water by Graphite Furnace Atomic Absorption Spectrophotometry,'' Open
File Report (OFR) 93-449.
\47\ ``Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Molybdenum by Graphite Furnace Atomic Absorption Spectrophotometry,'' Open File
Report (OFR) 97-198.
\48\ ``Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Total Phosphorus by Kjeldahl Digestion Method and an Automated Colorimetric Finish
That Includes Dialysis'' Open File Report (OFR) 92-146.
\49\ ``Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Arsenic and Selenium in Water and Sediment by Graphite Furnace-Atomic Absorption
Spectrometry'' Open File Report (OFR) 98-639.
\50\ ``Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Elements in Whole-water Digests Using Inductively Coupled Plasma-Optical Emission
Spectrometry and Inductively Coupled Plasma-Mass Spectrometry,'' Open File Report (OFR) 98-165.
\51\ ``Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Inorganic and Organic Constituents in Water and Fluvial Sediment,'' Open File
Report (OFR) 93-125.
\52\ All EPA methods, excluding EPA Method 300.1, are published in ``Methods for the Determination of Metals in Environmental Samples,'' Supplement I, National Exposure Risk Laboratory-
Cincinnati (NERL-CI), EPA/600/R-94/111, May 1994; and ``Methods for the Determination of Inorganic Substances in Environmental Samples,'' NERL-CI, EPA/600/R-93/100, August, 1993. EPA Method
300.1 is available from http://www.epa.gov/safewater/methods/pdfs/met300.pdf.
\53\ Styrene divinyl benzene beads (e.g., AMCO-AEPA-1 or equivalent) and stabilized formazin (e.g., Hach StablCal\TM\ or equivalent) are acceptable substitutes for formazin.
\54\ Method D6508, Rev. 2, ``Test Method for Determination of Dissolved Inorganic Anions in Aqueous Matrices Using Capillary Ion Electrophoresis and Chromate Electrolyte,'' available from
Waters Corp, 34 Maple St., Milford, MA, 01757, Telephone: 508/482-2131, Fax: 508/482-3625.
\55\ Kelada-01, ``Kelada Automated Test Methods for Total Cyanide, Acid Dissociable Cyanide, and Thiocyanate,'' EPA 821-B-01-009, Revision 1.2, August 2001, National Technical Information
Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161 [Order Number PB 2001-108275]. The toll free telephone number is: 800-553-6847. Note: A 450-W UV lamp may be used in this method
instead of the 550-W lamp specified if it provides performance within the quality control (QC) acceptance criteria of the method in a given instrument. Similarly, modified flow cell
configurations and flow conditions may be used in the method, provided that the QC acceptance criteria are met.
\56\ QuikChem Method 10-204-00-1-X, ``Digestion and Distillation of Total Cyanide in Drinking and Wastewaters using MICRO DIST and Determination of Cyanide by Flow Injection Analysis'' is
available from Lachat Instruments 6645 W. Mill Road, Milwaukee, WI 53218, Telephone: 414-358-4200.
\57\ When using sulfide removal test procedures described in Method 335.4, reconstitute particulate that is filtered with the sample prior to distillation.
\58\ Unless otherwise stated, if the language of this table specifies a sample digestion and/or distillation ``followed by'' analysis with a method, approved digestion and/or distillation are
required prior to analysis.
\59\ Method 245.7, Rev. 2.0, ``Mercury in Water by Cold Vapor Atomic Fluorescence Spectrometry,'' February 2005, EPA-821-R-05-001, available from the U.S. EPA Sample Control Center (operated
by CSC), 6101 Stevenson Avenue, Alexandria, VA 22304, Telephone: 703-461-2100, Fax: 703-461-8056.
[[Page 30]]
\60\ The use of EDTA may decrease method sensitivity in some samples. Analysts may omit EDTA provided that all method specified quality control acceptance criteria are met.
\61\ Samples analyzed for available cyanide using Methods OIA-1677 or D6888-04 that contain particulate matter may be filtered only after the ligand exchange reagents have been added to the
samples, because the ligand exchange process converts complexes containing available cyanide to free cyanide, which is not removed by filtration. Analysts are further cautioned to limit the
time between the addition of the ligand exchange reagents and sample analysis to no more than 30 minutes to preclude settling of materials in samples.
Table IC--List of Approved Test Procedures for Non-Pesticide Organic Compounds
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
EPA method number \2,7\ Other approved methods
--------------------------------------------------------------------------------------------------------------------------------------------------------------
Parameter \1\ Standard Methods
GC GC/MS HPLC [Edition(s)] Standard Methods Online ASTM Other
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1. Acenaphthene.................. 610 625, 1625B........... 610 6440 B [18th, 19th, 20th] ......................... D4657-92 (99)............ See footnote \9\, p. 27
2. Acenaphthylene................ 610 625, 1625B........... 610 6410 B, 6440 B, [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
3. Acrolein...................... 603 624 \4\, 1624B.......
4. Acrylonitrile................. 603 624 \4\, 1624B.......
5. Anthracene.................... 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
6. Benzene....................... 602 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th,19th], 6200 C
[20th] and 6220 B
[18th,19th].
7. Benzidine..................... ............ 625 \5\, 1625B....... 605 ......................... ......................... ......................... See footnote \3\, p.1
8. Benzo(a)anthracene............ 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
9. Benzo(a)pyrene................ 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
10. Benzo(b)fluoranthene......... 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
11. Benzo(g,h,i) perylene........ 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
12. Benzo(k) fluoranthene........ 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
13. Benzyl chloride.............. ............ ..................... ............ ......................... ......................... ......................... See footnote \3\, p. 130:
See footnote \6\, p.
S102
14. Benzyl butyl phthalate....... 606 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
[[Page 31]]
15. Bis(2-chloroethoxy) methane.. 611 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
16. Bis(2-chloroethyl) ether..... 611 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
17. Bis(2-ethylhexyl) phthalate.. 606 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
18. Bromodichloro-methane........ 601 624, 1624B........... ............ 6200 C [20th] and 6230 B 6200 B and C-97..........
[18th, 19th], 6200 B
[20th] and 6210 B [18th,
19th].
19. Bromoform.................... 601 624, 1624B........... ............ 6200 C [20th] and 6230 B 6200 B and C-97..........
[18th, 19th], 6200 B
[20th] and 6210 B [18th,
19th].
20. Bromomethane................. 601 624, 1624B........... ............ 6200 C [20th] and 6230 B 6200 B and C-97..........
[18th, 19th], 6200 B
[20th] and 6210 B [18th,
19th].
21. 4-Bromophenyl phenyl ether... 611 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
22. Carbon tetrachloride......... 601 624, 1624B........... ............ 6200 C [20th] and 6230 B 6200 C-97................ ......................... See footnote \3\, p. 130
[18th, 19th].
23. 4-Chloro-3-methyl phenol..... 604 625, 1625B........... ............ 6410 B, 6420 B [18th, 6410 B-00, 6420 B-00..... ......................... See footnote \9\, p. 27
19th, 20th].
24. Chlorobenzene................ 601, 602 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97.......... ......................... See footnote \3\, p. 130
[18th, 19th], 6200 C
[20th] and 6220 B [18th,
19th], 6200 C [20th] and
6230 B [18th, 19th].
25. Chloroethane................. 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
[[Page 32]]
26. 2-Chloroethylvinyl ether..... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
27. Chloroform................... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97.......... ......................... See footnote \3\, p. 130
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
28. Chloromethane................ 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th] 6200 C
[20th] and 6230 B [18th,
19th].
29. 2-Chloronaph-thalene......... 612 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
30. 2-Chlorophenol............... 604 625, 1625B........... ............ 6410 B, 6420 B [18th, 6410 B(00, 6420 B-00..... ......................... See footnote \9\, p. 27
19th, 20th].
31. 4-Chlorophenyl phenyl ether.. 611 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
32. Chrysene..................... 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
33. Dibenzo(a,h)an-thracene...... 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
34. Dibromochloro-methane........ 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th] 6200 C
[20th] and 6230 B [18th,
19th].
35. 1,2-Dichloro-benzene......... 601, 602 624, 1625B........... ............ 6200 C [20th] and 6220 B 6200 C-97................ ......................... See footnote \9\, p. 27
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
[[Page 33]]
36. 1,3-Dichloro-benzene......... 601, 602 624, 1625B........... ............ 6200 C [20th] and 6220 B 6200 C-97................ ......................... See footnote \9\, p. 27
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
37. 1,4-Dichloro-benzene......... 601, 602 624, 1625B........... ............ 6200 C [20th] and 6220 B 6200 C-97................ ......................... See footnote \9\, p. 27
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
38. 3,3-Dichloro-benzidine....... ............ 625, 1625B........... 605 6410 B [18th, 19th, 20th] 6410 B-00................
39. Dichlorodifluoro-methane..... 601 ..................... ............ 6200 C [20th] and 6230 B 6200 C-97................
[18th, 19th].
40. 1,1-Dichloroethane........... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
41. 1,2-Dichloroethane........... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
42. 1,1-Dichloroethene........... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
43. trans-1,2-Dichloro-ethene.... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
44. 2,4-Dichlorophenol........... 604 625, 1625B........... ............ 6410 B, 6420 B [18th, 6410 B-00, 6420 B-00..... ......................... See footnote \9\, p. 27
19th, 20th].
45. 1,2-Dichloro-propane......... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
[[Page 34]]
46. cis-1,3-Dichloro-propene..... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
47. trans-1,3-Dichloro-propene... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
48. Diethyl phthalate............ 606 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
49. 2,4-Dimethylphenol........... 604 625, 1625B........... ............ 6410 B, 6420 B [18th, 6410 B-00, 6420 B-00..... ......................... See footnote \9\, p. 27
19th, 20th].
50. Dimethyl phthalate........... 606 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
51. Di-n-butyl phthalate......... 606 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
52. Di-n-octyl phthalate......... 606 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
53. 2,3-Dinitrophenol............ 604 625, 1625B........... ............ 6410 B, 6420 B [18th, 6410 B-00, 6420 B-00..... ......................... .........................
19th, 20th].
54. 2,4-Dinitrotoluene........... 609 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
55. 2,6-Dinitrotoluene........... 609 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
56. Epichlorohydrin.............. ............ ..................... ............ ......................... ......................... ......................... See footnote \3\, p. 130;
See footnote \6\, p.
S102
57. Ethylbenzene................. 602 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97.......... ......................... .........................
[18th, 19th], 6200 C
[20th] and 6220 B [18th,
19th].
58. Fluoranthene................. 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
[[Page 35]]
59. Fluorene..................... 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
60. 1,2,3,4,6,7,8-Heptachloro- ............ 1613B \10\...........
dibenzofuran.
61. 1,2,3,4,7,8,9-Heptachloro- ............ 1613B \10\...........
dibenzofuran.
62. 1,2,3,4,6,7,8- ............ 1613B \10\...........
Heptachlorodibenzo-p-dioxin.
63. Hexachlorobenzene............ 612 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
64. Hexachloro-butadiene......... 612 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
65. Hexachlorocyclo-pentadiene... 612 625 \5\, 1625B....... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
66. 1,2,3,4,7,8- ............ 1613B \10\...........
Hexachlorodibenzofuran.
67. 1,2,3,6,7,8- ............ 1613B \10\...........
Hexachlorodibenzofuran.
68. 1,2,3,7,8,9- ............ 1613B \10\...........
Hexachlorodibenzofuran.
69. 2,3,4,6,7,8- ............ 1613B \10\...........
Hexachlorodibenzofuran.
70. 1,2,3,4,7,8-Hexachlorodibenzo- ............ 1613B \10\...........
p-dioxin.
71. 1,2,3,6,7,8-Hexachlorodibenzo- ............ 1613B \10\...........
p-dioxin.
72. 1,2,3,7,8,9-Hexachlorodibenzo- ............ 1613B \10\...........
p-dioxin 1613B \10\.
73. Hexachloroethane............. 612 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
74. Ideno(1,2,3-cd) pyrene....... 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
75. Isophorone................... 609 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
[[Page 36]]
76. Methylene chloride........... 601 624, 1624B........... ............ 6200 C [20th] and 6230 B 6200 C-97................ ......................... See footnote \3\, p. 130
[18th, 19th].
77. 2-Methyl-4,6-dinitrophenol... 604 625, 1625B........... ............ 6410 B, 6420 B [18th, 6410 B-00, 6420 B-00..... ......................... See footnote \9\, p. 27
19th, 20th].
78. Naphthalene.................. 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ ......................... See footnote \9\, p. 27
19th, 20th].
79. Nitrobenzene................. 609 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
80. 2-Nitrophenol................ 604 625, 1625B........... ............ 6410 B, 6420 B [18th, 6410 B-00, 6420 B-00..... ......................... See footnote \9\, p. 27
19th, 20th].
81. 4-Nitrophenol................ 604 625, 1625B........... ............ 6410 B, 6420 B [18th, 6410 B-00, 6420 B-00..... ......................... See footnote \9\, p. 27
19th, 20th].
82. N-Nitrosodimethylamine....... 607 6255, 1625B.......... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
83. N-Nitrosodi-n-propylamine.... 607 6255, 1625B.......... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
84. N-Nitrosodiphenylamine....... 607 6255, 1625B.......... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \9\, p. 27
85. Octachlorodibenzofuran....... ............ 1613B \10\*..........
86. Octachlorodibenzo-p-dioxin... ............ 1613B \10\...........
87. 2,2'-Oxybis(2-chloropropane) 611 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................
[also known as bis(2-
chloroisopropyl) ether].
88. PCB-1016..................... 608 625.................. ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \3\, p. 43;
See footnote \8\
89. PCB-1221..................... 608 625.................. ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \3\, p. 43;
See footnote \8\
90. PCB-1232..................... 608 625.................. ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \3\, p. 43;
See footnote \8\
[[Page 37]]
91. PCB-1242..................... 608 625.................. ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \3\, p. 43;
See footnote \8\
92. PCB-1248..................... 608 625..................
93. PCB-1254..................... 608 625.................. ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \3\, p. 43;
See footnote \8\
94. PCB-1260..................... 608 625.................. ............ 6410 B, 6630 B [18th, 6410 B-00................ ......................... See footnote 3, p. 43;
19th, 20th]. See footnote 8
95. 1,2,3,7,8-Pentachloro- ............ 1613B\10\............
dibenzofuran.
96. 2,3,4,7,8-Pentachloro- ............ 1613B\10\............
dibenzofuran.
97. 1,2,3,7,8,-Pentachlorodibenzo- ............ 1613B\10\............
p-dioxin.
98. Pentachlorophenol............ 604 625, 1625B........... ............ 6410 B, 6630 B [18th, 6410 B-00................ ......................... See footnote \3\, p. 140;
19th, 20th]. See footnote \9\, p. 27
99. Phenanthrene................. 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
100. Phenol...................... 604 625, 1625B........... ............ 6410 B, 6420 B [18th, 6410 B-00, 6420 B-00..... ......................... See footnote \9\, p. 27
19th, 20th].
101. Pyrene...................... 610 625, 1625B........... 610 6410 B, 6440 B [18th, 6410 B-00................ D4657-92 (99)............ See footnote \9\, p. 27
19th, 20th].
102. 2,3,7,8-Tetra- ............ 1613B10..............
chlorodibenzofuran.
103. 2,3,7,8-Tetra-chlorodibenzo- ............ 613, 625 \5a\, 1613B
p-dioxin. \10\.
104. 1,1,2,2-Tetra-chloro ethane. 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97.......... ......................... See footnote \3\, p. 130
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
105. Tetrachloroethene........... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97.......... ......................... See footnote \3\, p. 130
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
[[Page 38]]
106. Toluene..................... 602 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6220 B [18th,
19th].
107. 1,2,4-Trichloro-benzene..... 612 625, 1625B........... ............ 6410 B [18th, 19th, 20th] 6410 B-00................ ......................... See footnote \3\, p. 130;
See footnote \9\, p. 27
108. 1,1,1-Trichloro-ethane...... 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
109. 1,1,2-Trichloro-ethane...... 601 624, 1624B........... 6200 B 6200 B and C-97.......... ......................... See footnote \3\, p. 130.
[20th] and
6210 B
[18th,
19th], 6200
C [20th] and
6230 B
[18th, 19th]
110. Trichloroethene............. 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
111. Trichlorofluoro-methane..... 601 624.................. ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C
[20th] and 6230 B [18th,
19th].
112. 2,4,6-Trichlorophenol....... 604 625, 1625B........... ............ 6410 B, 6420 B [18th, 6410 B-00, 6420 B-00..... ......................... See footnote \9\, p. 27
19th, 20th].
[[Page 39]]
113. Vinyl chloride.............. 601 624, 1624B........... ............ 6200 B [20th] and 6210 B 6200 B and C-97..........
[18th, 19th], 6200 C [20th] and
6230 B [18th, 19th].
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ All parameters are expressed in micrograms per liter ([mu]g/L) except for Method 1613B in which the parameters are expressed in picograms per liter (pg/L).
\2\ The full text of Methods 601-613, 624, 625, 1624B, and 1625B, are given at Appendix A, ``Test Procedures for Analysis of Organic Pollutants,'' of this part 136. The full text of Method
1613B is incorporated by reference into this part 136 and is available from the National Technical Information Services as stock number PB95-104774. The standardized test procedure to be
used to determine the method detection limit (MDL) for these test procedures is given at Appendix B, ``Definition and Procedure for the Determination of the Method Detection Limit,'' of this
part 136.
\3\ ``Methods for Benzidine: Chlorinated Organic Compounds, Pentachlorophenol and Pesticides in Water and Wastewater,'' U.S. Environmental Protection Agency, September, 1978.
\4\ Method 624 may be extended to screen samples for Acrolein and Acrylonitrile. However, when they are known to be present, the preferred method for these two compounds is Method 603 or
Method 1624B.
\5\ Method 625 may be extended to include benzidine, hexachlorocyclopentadiene, N-nitrosodimethylamine, and N-nitrosodiphenylamine. However, when they are known to be present, Methods 605,
607, and 612, or Method 1625B, are preferred methods for these compounds.
\5a\ 625, screening only.
\6\ ``Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency,'' Supplement to the Fifteenth Edition of Standard Methods for the Examination of
Water and Wastewater (1981).
\7\ Each analyst must make an initial, one-time demonstration of their ability to generate acceptable precision and accuracy with Methods 601-603, 624, 625, 1624B, and 1625B (See appendix A of
this part 136) in accordance with procedures each in Section 8.2 of each of these methods. Additionally, each laboratory, on an on-going basis must spike and analyze 10% (5% for methods 624
and 625 and 100% for methods 1624B and 1625B) of all samples to monitor and evaluate laboratory data quality in accordance with Sections 8.3 and 8.4 of these methods. When the recovery of
any parameter falls outside the warning limits, the analytical results for that parameter in the unspiked sample are suspect. The results should be reported, but cannot be used to
demonstrate regulatory compliance. These quality control requirements also apply to the Standard Methods, ASTM Methods, and other methods cited.
\8\ ``Organochlorine Pesticides and PCBs in Wastewater Using Empore\TM\ Disk'' 3M Corporation Revised 10/28/94.
\9\ USGS Method 0-3116-87 from ``Methods of Analysis by U.S. Geological Survey National Water Quality Laboratory--Determination of Inorganic and Organic Constituents in Water and Fluvial
Sediments,'' U.S. Geological Survey, Open File Report 93-125.
\10\ Analysts may use Fluid Management Systems, Inc. PowerPrep system in place of manual cleanup provided that the analysis meet the requirements of Method 1613B (as specified in Section 9 of
the method) and permitting authorities.
Table ID--List of Approved Test Procedures for Pesticides \1\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
EPA \2,\ Standard Methods 18th,
Parameter Method \7\ 19th, 20th Ed. Standard Methods Online ASTM Other
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1. Aldrin........................ GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \4\, p.
D5812-96 (2002)......... 27; See footnote \8\
GC/MS............... 625 6410 B.................. 6410 B-00...............
2. Ametryn....................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 83; See footnote \6\, p
S68
3. Aminocarb..................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 94; See footnote \6\,
p. S16
4. Atraton....................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 83; See footnote \6\,
p. S68
[[Page 40]]
5. Atrazine...................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 83; See footnote \6\,
p. S68; See footnote \9\
6. Azinphos methyl............... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 25; See footnote \6\,
p. S51
7. Barban........................ TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
8. [alpha]-BHC................... GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \8\
D5812-96(02)............
GC/MS............... 625 \5\ 6410 B.................. 6410 B-00...............
9. [beta]-BHC.................... GC.................. 608 6630 C.................. ........................ D3086-90,............... See footnote \8\
D5812-96(02)............
GC/MS............... 625 \5\ 6410 B.................. 6410 B-00...............
10. [delta]-BHC.................. GC.................. 608 6630 C.................. ........................ D3086-90,............... See footnote \8\
D5812-96(02)............
GC/MS............... 625 \5\ 6410 B.................. 6410 B-00...............
11. [gamma]-BHC (Lindane)........ GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \4\, p.
D5812-96(02)............ 27; See footnote \8\
GC/MS............... 625 6410 B.................. 6410 B-00...............
....................
12. Captan....................... GC.................. ........... 6630 B.................. ........................ D3086-90,............... See footnote \3\, p. 7
D5812-96(02)............
13. Carbaryl..................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 94, See footnote \6\,
p. S60
14. Carbo-phenothion............. GC.................. ........... ........................ ........................ ........................ See footnote \4\, p. 27; See footnote \6\,
p. S73
15. Chlordane.................... GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \4\, p.
D5812-96(02)............ 27; See footnote \8\
GC/MS............... 625 6410 B.................. 6410 B-00...............
16. Chloro-propham............... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64.
17. 2,4-D........................ GC.................. ........... 6640 B.................. ........................ ........................ See footnote \3\, p. 115; See footnote \4\,
p. 40
18. 4,4[min]-DDD................. GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \4\, p.
D5812-96(02)............ 27; See footnote \8\
GC/MS............... 625 6410 B.................. 6410 B-00...............
19. 4,4[min]-DDE................. GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \4\, p.
D5812-96(02)............ 27; See footnote \8\
GC/MS............... 625 6410 B.................. 6410 B-00...............
[[Page 41]]
20. 4,4[min]-DDT................. GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \4\, p.
D5812-96(02)............ 27; See footnote \8\
GC/MS............... 625 6410 B.................. 6410 B-00...............
21. Demeton-O.................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 25; See footnote \6\,
p. S51
22. Demeton-S.................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 25; See footnote \6\,
p. S51
23. Diazinon..................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 25; See footnote \4\,
p. 27; See footnote \6\, p. S51
24. Dicamba...................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 115
25. Dichlofen-thion.............. GC.................. ........... ........................ ........................ ........................ See footnote \4\, p. 27; See footnote \6\,
p. S73
26. Dichloran.................... GC.................. ........... 6630 B & C.............. ........................ ........................ See footnote \3\, p. 7
27. Dicofol...................... GC.................. ........... ........................ ........................ D3086-90,...............
D5812-96(02)............
28. Dieldrin..................... GC.................. 608 6630 B & C.............. ........................ ........................ See footnote \3\, p. 7; See footnote \4\, p.
27; See footnote \8\
GC/MS............... 625 6410 B.................. 6410 B-00...............
29. Dioxathion................... GC.................. ........... ........................ ........................ ........................ See footnote \4\, p. 27; See footnote \6\,
p. S73
30. Disulfoton................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 25; See footnote \6\,
p. S51
31. Diuron....................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
32. Endosulfan I................. GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \4\, p.
D5812-96(02)............ 27; See footnote \8\
GC/MS............... 625 \5\ 6410 B.................. 6410 B-00...............
33. Endosulfan II................ GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \8\
D5812-96(02)............
GC/MS............... 625 \5\ 6410 B.................. 6410 B-00...............
34. Endosulfan Sulfate........... GC.................. 608 6630 C.................. ........................ ........................ See footnote \8\
GC/MS............... 625 6410 B.................. 6410 B-00...............
35. Endrin....................... GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \4\, p.
D5812-96(02)............ 27; See footnote \8\
GC/MS............... 625 \5\ 6410 B.................. 6410 B-00...............
36. Endrin aldehyde.............. GC.................. 608 ........................ ........................ ........................ See footnote \8\
GC/MS............... 625
37. Ethion....................... GC.................. ........... ........................ ........................ ........................ See footnote \4\, p. 27; See footnote \6\,
p. S73
38. Fenuron...................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
39. Fenuron-TCA.................. TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
[[Page 42]]
40. Heptachlor................... GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \4\, p.
GC/MS............... 625 6410 B.................. 6410 B-00............... D5812-96(02)............ 27; See footnote \8\
41. Heptachlor epoxide........... GC.................. 608 6630 B & C.............. ........................ D3086-90,............... See footnote \3\, p. 7; See footnote \4\, p.
GC/MS............... 625 6410 B.................. 6410 B-00............... D5812- 96(02)........... 27; See footnote \6\, p. S73; See footnote
\8\
42. Isodrin...................... GC.................. ........... ........................ ........................ ........................ See footnote \4\, p. 27; See footnote \6\,
p. S73
43. Linuron...................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
44. Malathion.................... GC.................. ........... 6630 C.................. ........................ ........................ See footnote \3\, p. 25; See footnote \4\,
p. 27; See footnote \6\, p. S51
45. Methiocarb................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 94; See footnote \6\,
p. S60
46. Methoxy-chlor................ GC.................. ........... 6630 B & C.............. ........................ D3086-90, D5812-96(02).. See footnote \3\, p. 7; See footnote \4\, p.
27; See footnote \8\
47. Mexacar-bate................. TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 94; See footnote \6\,
p. S60
48. Mirex........................ GC.................. ........... 6630 B & C.............. ........................ ........................ See footnote \3\, p. 7; See footnote \4\, p.
27
49. Monuron...................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
50. Monuron-TCA.................. TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
51. Nuburon...................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
52. Parathion methyl............. GC.................. ........... 6630 C.................. ........................ ........................ See footnote \3\, p. 25; See footnote \4\,
p. 27
53. Parathion ethyl.............. GC.................. ........... 6630 C.................. ........................ ........................ See footnote \3\, p. 25; See footnote \4\,
p. 27
54. PCNB......................... GC.................. ........... 6630 B & C.............. ........................ ........................ See footnote \3\, p. 7
55. Perthane..................... GC.................. ........... ........................ ........................ D3086-90, D5812-96(02).. See footnote \4\, p. 27
56. Prometon..................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 83; See footnote \6\,
p. S68; See footnote \9\
57. Prometryn.................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 83; See footnote \6\,
p. S68; See footnote \9\
58. Propazine.................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 83; See footnote \6\,
p. S68; See footnote \9\
[[Page 43]]
59. Propham...................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
60. Propoxur..................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 94; See footnote \6\,
p. S60
61. Secbumeton................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 83; See footnote \6\,
p. S68
62. Siduron...................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
63. Simazine..................... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 83; See footnote \6\,
p. S68; See footnote \9\
64. Strobane..................... GC.................. ........... 6630 B & C.............. ........................ ........................ See footnote \3\, p. 7
65. Swep......................... TLC................. ........... ........................ ........................ ........................ See footnote \3\, p. 104; See footnote \6\,
p. S64
66. 2,4,5-T...................... GC.................. ........... 6640 B.................. ........................ ........................ See footnote \3\, p. 115; See footnote \4\,
p. 40
67. 2,4,5-TP (Silvex)............ GC.................. ........... 6640 B.................. ........................ ........................ See footnote \3\, p. 115; See footnote \4\,
p. 40
68. Terbuthylazine............... GC.................. ........... ........................ ........................ ........................ See footnote \3\, p. 83; See footnote \6\,
p. S68
69. Toxaphene.................... GC.................. 608 6630 B & C.............. ........................ D3086-90, D5812-96(02).. See footnote \3\, p. 7; See footnote \4\, p.
27; See footnote \8\
GC/MS............... 625 6410 B.................. 6410 B-00...............
70. Trifluralin.................. GC.................. ........... 6630 B.................. ........................ ........................ See footnote \3\, p. 7; See footnote \9\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Pesticides are listed in this table by common name for the convenience of the reader. Additional pesticides may be found under Table IC, where entries are listed by chemical name.
\2\ The full text of Methods 608 and 625 are given at Appendix A, ``Test Procedures for Analysis of Organic Pollutants,'' of this part 136. The standardized test procedure to be used to
determine the method detection limit (MDL) for these test procedures is given at Appendix B, ``Definition and Procedure for the Determination of the Method Detection Limit,'' of this part
136.
\3\ ``Methods for Benzidine, Chlorinated Organic Compounds, Pentachlorophenol and Pesticides in Water and Wastewater,'' U.S. Environmental Protection Agency, September 1978. This EPA
publication includes thin-layer chromatography (TLC) methods.
\4\``Methods for Analysis of Organic Substances in Water and Fluvial Sediments,'' Techniques of Water-Resources Investigations of the U.S. Geological Survey, Book 5, Chapter A3 (1987).
\5\ The method may be extended to include [alpha]-BHC, [gamma]-BHC, endosulfan I, endosulfan II, and endrin. However, when they are known to exist, Method 608 is the preferred method.
\6\ ``Selected Analytical Methods Approved and Cited by the United States Environmental Protection Agency.'' Supplement to the Fifteenth Edition of Standard Methods for the Examination of
Water and Wastewater (1981).
\7\ Each analyst must make an initial, one-time, demonstration of their ability to generate acceptable precision and accuracy with Methods 608 and 625 (See appendix A of this part 136) in
accordance with procedures given in Section 8.2 of each of these methods. Additionally, each laboratory, on an on-going basis, must spike and analyze 10% of all samples analyzed with Method
608 or 5% of all samples analyzed with Method 625 to monitor and evaluate laboratory data quality in accordance with Sections 8.3 and 8.4 of these methods. When the recovery of any parameter
falls outside the warning limits, the analytical results for that parameter in the unspiked sample are suspect. The results should be reported, but cannot be used to demonstrate regulatory
compliance. These quality control requirements also apply to the Standard Methods, ASTM Methods, and other methods cited.
\8\ ``Organochlorine Pesticides and PCBs in Wastewater Using Empore\TM\ Disk'', 3M Corporation, Revised 10/28/94.
\9\ USGS Method 0-3106-93 from ``Methods of Analysis by the U.S. Geological Survey National Water Quality Laboratory--Determination of Triazine and Other Nitrogen-containing Compounds by Gas
Chromatography with Nitrogen Phosphorus Detectors'' U.S. Geological Survey Open File Report 94-37.
[[Page 44]]
Table IE--List of Approved Radiologic Test Test Procedures
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Reference (method number or page)
--------------------------------------------------------------------------------------------------------------------------------------
Parameter and units Method Standard Methods 18th,
EPA \1\ 19th, 20th Ed. Standard Methods Online ASTM USGS \2\
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1. Alpha-Total, pCi per liter..... Proportional or 900.0................ 7110 B.................... 7110 B-00................. D1943-90, 96.............. pp. 75 and 78 \3\
scintillation
counter.
2. Alpha-Counting error, pCi per Proportional or Appendix B........... 7110 B.................... 7110 B-00................. D1943-90, 96.............. p. 79
liter. scintillation
counter.
3. Beta-Total, pCi per liter...... Proportional counter. 900.0................ 7110 B.................... 7110 B-00................. D1890-90, 96.............. pp. 75 and 78 \3\
4. Beta-Counting error, pCi....... Proportional counter. Appendix B........... 7110 B.................... 7110 B-00................. D1890-90, 96.............. p. 79
5. (a) Radium Total pCi per liter. Proportional counter. 903.0................ 7500-Ra B................. 7500-Ra B-01.............. D2460-90, 97.............. ..........................
(b) Ra, pCi per liter.............
Scintillation counter 903.1................ 7500-Ra C................. 7500-Ra C-01.............. D3454-91, 97.............. p. 81
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Prescribed Procedures for Measurement of Radioactivity in Drinking Water, EPA-600/4-80-032 (1980), U.S. Environmental Protection Agency, August 1980.
\2\ Fishman, M. J. and Brown, Eugene, ``Selected Methods of the U.S. Geological Survey of Analysis of Wastewaters,'' U.S. Geological Survey, Open-File Report 76-177 (1976).
\3\ The method found on p. 75 measures only the dissolved portion while the method on p. 78 measures only the suspended portion. Therefore, the two results must be added to obtain the
``total.''
[[Page 45]]
Table IF--List of Approved Methods for Pharmaceutical Pollutants
----------------------------------------------------------------------------------------------------------------
Pharmaceuticals pollutants CAS registry No. Analytical method number
----------------------------------------------------------------------------------------------------------------
acetonitrile................... 75-05-8............................ 1666/1671/D3371/D3695.
n-amyl acetate................. 628-63-7........................... 1666/D3695.
n-amyl alcohol................. 71-41-0............................ 1666/D3695
benzene........................ 71-43-2............................ D4763/D3695/502.2/524.2.
n-butyl-acetate................ 123-86-4........................... 1666/D3695.
tert-butyl alcohol............. 75-65-0............................ 1666.
chlorobenzene.................. 108-90-7........................... 502.2/524.2.
chloroform..................... 67-66-3............................ 502.2/524.2/551.
o-dichlorobenzene.............. 95-50-1............................ 1625C/502.2/524.2.
1,2-dichloroethane............. 107-06-2........................... D3695/502.2/524.2.
diethylamine................... 109-89-7........................... 1666/1671.
dimethyl sulfoxide............. 67-68-5............................ 1666/1671.
ethanol........................ 64-17-5............................ 1666/1671/D3695.
ethyl acetate.................. 141-78-6........................... 1666/D3695.
n-heptane...................... 142-82-5........................... 1666/D3695.
n-hexane....................... 110-54-3........................... 1666/D3695.
isobutyraldehyde............... 78-84-2............................ 1666/1667.
isopropanol.................... 67-63-0............................ 1666/D3695.
isopropyl acetate.............. 108-21-4........................... 1666/D3695.
isopropyl ether................ 108-20-3........................... 1666/D3695.
methanol....................... 67-56-1............................ 1666/1671/D3695.
Methyl Cellosolve [Delta]...... 109-86-4........................... 1666/1671
methylene chloride............. 75-09-2............................ 502.2/524.2
methyl formate................. 107-31-3........................... 1666.
4-methyl-2-pentanone (MIBK).... 108-10-1........................... 1624C/1666/D3695/D4763/524.2.
phenol......................... 108-95-2........................... D4763.
n-propanol..................... 71-23-8............................ 1666/1671/D3695.
2-propanone (acetone).......... 67-64-1............................ D3695/D4763/524.2.
tetrahydrofuran................ 109-99-9........................... 1666/524.2.
toluene........................ 108-88-3........................... D3695/D4763/502.2/524.2.
triethlyamine.................. 121-44-8........................... 1666/1671.
xylenes........................ (Note 1)........................... 1624C/1666.
----------------------------------------------------------------------------------------------------------------
Table 1F note:
1. 1624C: m-xylene 108-38-3, o,p-xylene E-14095 (Not a CAS number; this is the number provided in the
Environmental Monitoring Methods Index (EMMI) database.); 1666: m,p-xylene 136777-61-2, o-xylene 95-47-6.
Table IG--Test Methods for Pesticide Active Ingredients
----------------------------------------------------------------------------------------------------------------
EPA Survey Code Pesticide name CAS No. EPA Analytical Method No.(s)
----------------------------------------------------------------------------------------------------------------
8.................. Triadimefon.............. 43121-43-3 507/633/525.1/1656
12................. Dichlorvos............... 62-73-7 1657/507/622/525.1
16................. 2,4-D; 2,4-D Salts and 94-75-7 1658/515.1/615/515.2/555
Esters [2,4-Dichloro-
phenoxyacetic acid].
17................. 2,4-DB; 2,4-DB Salts and 94-82-6 1658/515.1/615/515.2/555
Esters [2,4-
Dichlorophenoxybutyric
acid].
22................. Mevinphos................ 7786-34-7 1657/507/622/525.1
25................. Cyanazine................ 21725-46-2 629/507
26................. Propachlor............... 1918-16-7 1656/508/608.1/525.1
27................. MCPA; MCPA Salts and 94-74-6 1658/615/555
Esters [2-Methyl-4-
chlorophenoxyacetic
acid].
30................. Dichlorprop; Dichlorprop 120-36-5 1658/515.1/615/515.2/555
Salts and Esters [2-(2,4-
Dichlorophenoxy)
propionic acid].
31................. MCPP; MCPP Salts and 93-65-2 1658/615/555
Esters [2-(2-Methyl-4-
chlorophenoxy) propionic
acid].
35................. TCMTB [2- 21564-17-0 637
(Thiocyanomethylthio)
benzo-thiazole].
39................. Pronamide................ 23950-58-5 525.1/507/633.1
41................. Propanil................. 709-98-8 632.1/1656
45................. Metribuzin............... 21087-64-9 507/633/525.1/1656
52................. Acephate................. 30560-19-1 1656/1657
[[Page 46]]
53................. Acifluorfen.............. 50594-66-6 515.1/515.2/555
54................. Alachlor................. 15972-60-8 505/507/645/525.1/1656
55................. Aldicarb................. 116-06-3 531.1
58................. Ametryn.................. 834-12-8 507/619/525.1
60................. Atrazine................. 1912-24-9 505/507/619/525.1/1656
62................. Benomyl.................. 17804-35-2 631
68................. Bromacil; Bromacil Salts 314-40-9 507/633/525.1/1656
and Esters.
69................. Bromoxynil............... 1689-84-5 1625/1661
69................. Bromoxynil octanoate..... 1689-99-2 1656
70................. Butachlor................ 23184-66-9 507/645/525.1/1656
73................. Captafol................. 2425-06-1 1656
75................. Carbaryl [Sevin]......... 63-25-2 531.1/632/553
76................. Carbofuran............... 1563-66-2 531.1/632
80................. Chloroneb................ 2675-77-6 1656/508/608.1/525.1
82................. Chlorothalonil........... 1897-45-6 508/608.2/525.1/1656
84................. Stirofos................. 961-11-5 1657/507/622/525.1
86................. Chlorpyrifos............. 2921-88-2 1657/508/622
90................. Fenvalerate.............. 51630-58-1 1660
103................ Diazinon................. 333-41-5 1657/507/614/622/525.1
107................ Parathion methyl......... 298-00-0 1657/614/622
110................ DCPA [Dimethyl 2,3,5,6- 1861-32-1 508/608.2/525.1/515.1/515.2/1656
tetrachloro-
terephthalate].
112................ Dinoseb.................. 88-85-7 1658/515.1/615/515.2/555
113................ Dioxathion............... 78-34-2 1657/614.1
118................ Nabonate [Disodium 138-93-2 630.1
cyanodithio-
imidocarbonate].
119................ Diuron................... 330-54-1 632/553
123................ Endothall................ 145-73-3 548/548.1
124................ Endrin................... 72-20-8 1656/505/508/608/617/525.1
125................ Ethalfluralin............ 55283-68-6 1656/627 See footnote 1
126................ Ethion................... 563-12-2 1657/614/614.1
127................ Ethoprop................. 13194-48-4 1657/507/622/525.1
132................ Fenarimol................ 60168-88-9 507/633.1/525.1/1656
133................ Fenthion................. 55-38-9 1657/622
138................ Glyphosate 1071-83-6 547
[N(Phosphonomethyl)
glycine].
140................ Heptachlor............... 76-44-8 1656/505/508/608/617/525.1
144................ Isopropalin.............. 33820-53-0 1656/627
148................ Linuron.................. 330-55-2 553/632
150................ Malathion................ 121-75-5 1657/614
154................ Methamidophos............ 10265-92-6 1657
156................ Methomyl................. 16752-77-5 531.1/632
158................ Methoxychlor............. 72-43-5 1656/505/508/608.2/617/525.1
172................ Nabam.................... 142-59-6 630/630.1
173................ Naled.................... 300-76-5 1657/622
175................ Norflurazon.............. 27314-13-2 507/645/525.1/1656
178................ Benfluralin.............. 1861-40-1 11656/1627
182................ Fensulfothion............ 115-90-2 1657/622
183................ Disulfoton............... 298-04-4 1657/507/614/622/525.1
185................ Phosmet.................. 732-11-6 1657/622.1
186................ Azinphos Methyl.......... 86-50-0 1657/614/622
192................ Organo-tin pesticides.... 12379-54-3 Ind-01/200.7/200.9
197................ Bolstar.................. 35400-43-2 1657/622
203................ Parathion................ 56-38-2 1657/614
204................ Pendimethalin............ 40487-42-1 1656
205................ Pentachloronitrobenzene.. 82-68-8 1656/608.1/617
206................ Pentachlorophenol........ 87-86-5 625/1625/515.2/555/515.1/ 525.1
208................ Permethrin............... 52645-53-1 608.2/508/525.1/1656/1660
212................ Phorate.................. 298-02-2 1657/622
218................ Busan 85 [Potassium 128-03-0 630/630.1
dimethyldithiocarbamate].
[[Page 47]]
219................ Busan 40 [Potassium N- 51026-28-9 630/630.1
hydroxymethyl-N-
methyldithiocarbamate].
220................ KN Methyl [Potassium N- 137-41-7 630/630.1
methyl-dithiocarbamate].
223................ Prometon................. 1610-18-0 507/619/525.1
224................ Prometryn................ 7287-19-6 507/619/525.1
226................ Propazine................ 139-40-2 507/619/525.1/1656
230................ Pyrethrin I.............. 121-21-1 1660
232................ Pyrethrin II............. 121-29-9 1660
236................ DEF [S,S,S-Tributyl 78-48-8 1657
phosphorotrithioate].
239................ Simazine................. 122-34-9 505/507/619/525.1/1656
241................ Carbam-S [Sodium 128-04-1 630/630.1
dimethyldithiocarbanate].
243................ Vapam [Sodium 137-42-8 630/630.1
methyldithiocarbamate].
252................ Tebuthiuron.............. 34014-18-1 507/525.1
254................ Terbacil................. 5902-51-2 507/633/525.1/1656
255................ Terbufos................. 13071-79-9 1657/507/614.1/525.1
256................ Terbuthylazine........... 5915-41-3 619/1656
257................ Terbutryn................ 886-50-0 507/619/525.1
259................ Dazomet.................. 533-74-4 630/630.1/1659
262................ Toxaphene................ 8001-35-2 1656/505/508/608/617/525.1
263................ Merphos [Tributyl 150-50-5 1657/507/525.1/622
phosphorotrithioate].
264................ Trifluralin.............. 1582-09-8 1656/508/617/627/525.1
268................ Ziram [Zinc 137-30-4 630/630.1
dimethyldithiocarbamate].
----------------------------------------------------------------------------------------------------------------
\1\ Monitor and report as total Trifluralin.
[[Page 48]]
Table IH--List of Approved Microbiological Methods for Ambient Water
--------------------------------------------------------------------------------------------------------------------------------------------------------
Standard methods
Parameter and units Method \1\ EPA 18th, 19th, 20th Standard methods AOAC, ASTM, USGS Other
Ed. online
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bacteria:
1. E. coli, number per 100 MPN \6,8,14\ .................. 9221 B.1/9221 F 9221 B.1-99/9221 F
mL. multiple tube, \11,13\. \11,13\.
Multiple tube/ .................. 9223 B \12\....... 9223 B-97 \12\.... 991.15 \10\....... Colilert[reg]
multiple well, \12,16\ Colilert-
18[reg]
\12,15,16\.
MF \2,5,6,7,8\ two 1103.1 \19\....... 9222 B/9222 G 9222 B-97/9222 G D5392-93 \9\......
step, or \18\, 9213 D. \18\.
Single step....... 1603 \20\, 1604 .................. .................. .................. mColiBlue-24[reg]
\21\. \17\.
2. Enterococci, number per MPN \6,8\ multiple .................. 9230 B............ 9230 B-93.........
100 mL. tube,
Multiple tube/ .................. .................. .................. D6503-99 \9\...... Enterolert[reg]
multiple well. \12,22\.
MF \2,5,6,7,8\ two 1106.1 \23\....... 9230 C............ 9230 C-93......... D5259-92 \9\......
step.
Single step, or... 1600 \24\.........
Plate count....... p. 143 \3\........
Protozoa:
3. Cryptosporidium.......... Filtration/IMS/FA. 1622 \25,\1623
\26\.
4. Giardia.................. Filtration/IMS/FA. 1623 \26\.........
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The method must be specified when results are reported.
\2\ A 0.45 [mu]m membrane filter (MF) or other pore size certified by the manufacturer to fully retain organisms to be cultivated and to be free of
extractables which could interfere with their growth.
\3\ USEPA. 1978. Microbiological Methods for Monitoring the Environment, Water, and Wastes. Environmental Monitoring and Support Laboratory, U.S.
Environmental Protection Agency, Cincinnati, OH. EPA/600/8-78/017.
\4\ [Reserved]
\5\ Because the MF technique usually yields low and variable recovery from chlorinated wastewaters, the Most Probable Number method will be required to
resolve any controversies.
\6\ Tests must be conducted to provide organism enumeration (density). Select the appropriate configuration of tubes/filtrations and dilutions/volumes
to account for the quality, character, consistency, and anticipated organism density of the water sample.
\7\ When the MF method has not been used previously to test waters with high turbidity, large number of noncoliform bacteria, or samples that may
contain organisms stressed by chlorine, a parallel test should be conducted with a multiple-tube technique to demonstrate applicability and
comparability of results.
\8\ To assess the comparability of results obtained with individual methods, it is suggested that side-by-side tests be conducted across seasons of the
year with the water samples routinely tested in accordance with the most current Standard Methods for the Examination of Water and Wastewater or EPA
alternate test procedure (ATP) guidelines.
\9\ ASTM. 2000, 1999, 1996. Annual Book of ASTM Standards--Water and Environmental Technology. Section 11.02. ASTM International. 100 Barr Harbor Drive,
West Conshohocken, PA 19428.
\10\ AOAC. 1995. Official Methods of Analysis of AOAC International, 16th Edition, Volume I, Chapter 17. Association of Official Analytical Chemists
International. 481 North Frederick Avenue, Suite 500, Gaithersburg, MD 20877-2417.
\11\ The multiple-tube fermentation test is used in 9221B.1. Lactose broth may be used in lieu of lauryl tryptose broth (LTB), if at least 25 parallel
tests are conducted between this broth and LTB using the water samples normally tested, and this comparison demonstrates that the false-positive rate
and false-negative rate for total coliform using lactose broth is less than 10 percent. No requirement exists to run the completed phase on 10 percent
of all total coliform-positive tubes on a seasonal basis.
\12\ These tests are collectively known as defined enzyme substrate tests, where, for example, a substrate is used to detect the enzyme [beta]-
glucuronidase produced by E. coli.
\13\ After prior enrichment in a presumptive medium for total coliform using 9221B.1, all presumptive tubes or bottles showing any amount of gas, growth
or acidity within 48 h 3 h of incubation shall be submitted to 9221F. Commercially available EC-MUG media or EC media
supplemented in the laboratory with 50 [mu]g/mL of MUG may be used.
\14\ Samples shall be enumerated by the multiple-tube or multiple-well procedure. Using multiple-tube procedures, employ an appropriate tube and
dilution configuration of the sample as needed and report the Most Probable Number (MPN). Samples tested with Colilert[reg] may be enumerated with the
multiple-well procedures, Quanti-Tray[reg] or Quanti-Tray[reg] 2000, and the MPN calculated from the table provided by the manufacturer.
\15\ Colilert-18[reg] is an optimized formulation of the Colilert[reg] for the determination of total coliforms and E. coli that provides results within
18 h of incubation at 35 [deg]C rather than the 24 h required for the Colilert[reg] test and is recommended for marine water samples.
\16\ Descriptions of the Colilert[reg], Colilert-18[reg], Quanti-Tray[reg], and Quanti-Tray[reg]/2000 may be obtained from IDEXX Laboratories, Inc., 1
IDEXX Drive, Westbrook, ME 04092.
\17\ A description of the mColiBlue24[reg] test, Total Coliforms and E. coli, is available from Hach Company, 100 Dayton Ave., Ames, IA 50010.
\18\ Subject total coliform positive samples determined by 9222B or other membrane filter procedure to 9222G using NA-MUG media.
[[Page 49]]
\19\ USEPA. July 2006. Method 1103.1: Escherichia coli (E. coli) in Water by Membrane Filtration Using membrane-Thermotolerant Escherichia coli Agar
(mTEC). U.S. Environmental Protection Agency, Office of Water, Washington, DC EPA-821-R-06-010.
\20\ USEPA. July 2006. Method 1603: Escherichia coli (E. coli) in Water by Membrane Filtration Using Modified membrane-Thermotolerant Escherichia coli
Agar (Modified mTEC). U.S. Environmental Protection Agency, Office of Water, Washington, DC EPA-821-R-06-011.
\21\ Preparation and use of MI agar with a standard membrane filter procedure is set forth in the article, Brenner et al. 1993. ``New Medium for the
Simultaneous Detection of Total Coliform and Escherichia coli in Water.'' Appl. Environ. Microbiol. 59:3534-3544 and in USEPA. September 2002.: Method
1604: Total Coliforms and Escherichia coli (E. coli) in Water by Membrane Filtration by Using a Simultaneous Detection Technique (MI Medium). U.S.
Environmental Protection Agency, Office of Water, Washington, DC EPA 821-R-02-024.
\22\ A description of the Enterolert[reg] test may be obtained from IDEXX Laboratories, Inc., 1 IDEXX Drive, Westbrook, ME 04092.
\23\ USEPA. July 2006. Method 1106.1: Enterococci in Water by Membrane Filtration Using membrane-Enterococcus-Esculin Iron Agar (mE-EIA). U.S.
Environmental Protection Agency, Office of Water, Washington, DC EPA-821-R-06-008.
\24\ USEPA. July 2006. Method 1600: Enterococci in Water by Membrane Filtration Using membrane-Enterococcus Indoxyl-[beta]-D-Glucoside Agar (mEI). U.S.
Environmental Protection Agency, Office of Water, Washington, DC EPA-821-R-06-009.
\25\ Method 1622 uses filtration, concentration, immunomagnetic separation of oocysts from captured material, immunofluorescence assay to determine
concentrations, and confirmation through vital dye staining and differential interference contrast microscopy for the detection of Cryptosporidium.
USEPA. 2001. Method 1622: Cryptosporidium in Water by Filtration/IMS/FA. U.S. Environmental Protection Agency, Office of Water, Washington, DC EPA-821-
R-01-026.
\26\ Method 1623 uses filtration, concentration, immunomagnetic separation of oocysts and cysts from captured material, immunofluorescence assay to
determine concentrations, and confirmation through vital dye staining and differential interference contrast microscopy for the simultaneous detection
of Cryptosporidium and Giardia oocysts and cysts. USEPA. 2001. Method 1623. Cryptosporidium and Giardia in Water by Filtration/IMS/FA. U.S.
Environmental Protection Agency, Office of Water, Washington, DC EPA-821-R-01-025.
[[Page 50]]
(b) The full texts of the methods from the following references
which are cited in Tables IA, IB, IC, ID, IE, IF, IG and IH are
incorporated by reference into this regulation and may be obtained from
the source identified. All costs cited are subject to change and must be
verified from the indicated source. The full texts of all the test
procedures cited are available for inspection at the National Archives
and Records Administration (NARA). For information on the availability
of this material at NARA, call 202-741-6030, or go to: http://
www.archives.gov/federal--register/code--of--federal--regulations/ibr--
locations.html.
References, Sources, Costs, and Table Citations:
(1) The full texts of Methods 601-613, 624, 625, 1613, 1624, and
1625 are printed in appendix A of this part 136. The full text for
determining the method detection limit when using the test procedures is
given in appendix B of this part 136. The full text of Method 200.7 is
printed in appendix C of this part 136. Cited in: Table IB, Note 5;
Table IC, Note 2; and Table ID, Note 2.
(2) USEPA. 1978. Microbiological Methods for Monitoring the
Environment, Water, and Wastes. Environmental Monitoring and Support
Laboratory, U.S. Environmental Protection Agency, Cincinnati, Ohio. EPA/
600/8-78/017. Available at http://www.epa.gov/clariton/srch.htm or from:
National Technical Information Service, 5285 Port Royal Road,
Springfield, Virginia 22161, Pub. No. PB-290329/A.S. Table IA, Note 3;
Table IH, Note 3.
(3) ``Methods for Chemical Analysis of Water and Wastes,'' U.S.
Environmental Protection Agency, EPA-600/4-79-020, March 1979, or
``Methods for Chemical Analysis of Water and Wastes,'' U.S.
Environmental Protection Agency, EPA-600/4-79-020, Revised March 1983.
Available from: ORD Publications, CERI, U.S. Environmental Protection
Agency, Cincinnati, Ohio 45268, Table IB, Note 1.
(4) ``Methods for Benzidine, Chlorinated Organic Compounds,
Pentachlorophenol and Pesticides in Water and Wastewater,'' U.S.
Environmental Protection Agency, 1978. Available from: ORD Publications,
CERI, U.S. Environmental Protection Agency, Cincinnati, Ohio 45268,
Table IC, Note 3; Table D, Note 3.
(5) ``Prescribed Procedures for Measurement of Radioactivity in
Drinking Water,'' U.S. Environmental Protection Agency, EPA-600/4-80-
032, 1980. Available from: ORD Publications, CERI, U.S. Environmental
Protection Agency, Cincinnati, Ohio 45268, Table IE, Note 1.
(6) American Public Health Association. 1992, 1995, and 1998.
Standard Methods for the Examination of Water and Wastewater. 18th,
19th, and 20th Edition (respectively). Available from: American Public
Health Association, 1015 15th Street, NW., Washington, DC 20005.
Standard Methods Online is available through the Standard Methods Web
site (http://www.standardmethods.org). Tables IA, IB, IC, ID, IE, and
IH.
(7) Ibid, 15th Edition, 1980. Table IB, Note 30; Table ID.
(8) Ibid, 14th Edition, 1975. Table IB, Notes 17 and 27.
(9) ``Selected Analytical Methods Approved and Cited by the United
States Environmental Protection Agency,'' Supplement to the 15th Edition
of Standard Methods for the Examination of Water and Wastewater, 1981.
Available from: American Public Health Association, 1015 Fifteenth
Street NW., Washington, DC 20036. Cost available from publisher. Table
IB, Note 10; Table IC, Note 6; Table ID, Note 6.
(10) ASTM International. Annual Book of ASTM Standards, Water, and
Environmental Technology, Section 11, Volumes 11.01 and 11.02, 1994,
1996, 1999, Volume 11.02, 2000, and individual standards published after
2000. Available from: ASTM International, 100 Barr Harbor Drive, P.O.
Box C700, West Conshohocken, PA 19428-2959, or http://www.astm.org.
Tables IA, IB, IC, ID, IE, and IH.
(11) USGS. 1989. U.S. Geological Survey Techniques of Water-
Resources Investigations, Book 5, Laboratory Analysis, Chapter A4,
Methods for Collection and Analysis of Aquatic Biological and
Microbiological Samples, U.S. Geological Survey, U.S. Department of the
Interior, Reston, Virginia. Available
[[Page 51]]
from USGS Books and Open-File Reports Section, Federal Center, Box
25425, Denver, Colorado 80225. Table IA, Note 5; Table IH.
(12) ``Methods for Determination of Inorganic Substances in Water
and Fluvial Sediments,'' by M.J. Fishman and Linda C. Friedman,
Techniques of Water-Resources Investigations of the U.S. Geological
Survey, Book 5 Chapter A1 (1989). Available from: U.S. Geological
Survey, Denver Federal Center, Box 25425, Denver, CO 80225. Cost:
$108.75 (subject to change). Table IB, Note 2.
(13) ``Methods for Determination of Inorganic Substances in Water
and Fluvial Sediments,'' N.W. Skougstad and others, editors. Techniques
of Water-Resources Investigations of the U.S. Geological Survey, Book 5,
Chapter A1 (1979). Available from: U.S. Geological Survey, Denver
Federal Center, Box 25425, Denver, CO 80225. Cost: $10.00 (subject to
change), Table IB, Note 8.
(14) ``Methods for the Determination of Organic Substances in Water
and Fluvial Sediments,'' Wershaw, R.L., et al, Techniques of Water-
Resources Investigations of the U.S. Geological Survey, Book 5, Chapter
A3 (1987). Available from: U.S. Geological Survey, Denver Federal
Center, Box 25425, Denver, CO 80225. Cost: $0.90 (subject to change).
Table IB, Note 24; Table ID, Note 4.
(15) ``Water Temperature--Influential Factors, Field Measurement and
Data Presentation,'' by H.H. Stevens, Jr., J. Ficke, and G.F. Smoot,
Techniques of Water-Resources Investigations of the U.S. Geological
Survey, Book 1, Chapter D1, 1975. Available from: U.S. Geological
Survey, Denver Federal Center, Box 25425, Denver, CO 80225. Cost: $1.60
(subject to change). Table IB, Note 32.
(16) ``Selected Methods of the U.S. Geological Survey of Analysis of
Wastewaters,'' by M.J. Fishman and Eugene Brown; U.S. Geological Survey
Open File Report 76-77 (1976). Available from: U.S. Geological Survey,
Branch of Distribution, 1200 South Eads Street, Arlington, VA 22202.
Cost: $13.50 (subject to change). Table IE, Note 2.
(17) AOAC-International. Official Methods of Analysis of AOAC-
International, 16th Edition, (1995). Available from: AOAC-International,
481 North Frederick Avenue, Suite 500, Gaithersburg, MD 20877. Table IB,
See footnote 3.
(18) ``American National Standard on Photographic Processing
Effluents,'' April 2, 1975. Available from: American National Standards
Institute, 1430 Broadway, New York, New York 10018. Table IB, Note 9.
(19) ``An Investigation of Improved Procedures for Measurement of
Mill Effluent and Receiving Water Color,'' NCASI Technical Bulletin No.
253, December 1971. Available from: National Council of the Paper
Industry for Air and Stream Improvements, Inc., 260 Madison Avenue, New
York, NY 10016. Cost available from publisher. Table IB, Note 18.
(20) Ammonia, Automated Electrode Method, Industrial Method Number
379-75WE, dated February 19, 1976. Technicon Auto Analyzer II. Method
and price available from Technicon Industrial Systems, Tarrytown, New
York 10591. Table IB, Note 7.
(21) Chemical Oxygen Demand, Method 8000, Hach Handbook of Water
Analysis, 1979. Method price available from Hach Chemical Company, P.O.
Box 389, Loveland, Colorado 80537. Table IB, Note 14.
(22) OIC Chemical Oxygen Demand Method, 1978. Method and price
available from Oceanography International Corporation, 512 West Loop,
P.O. Box 2980, College Station, Texas 77840. Table IB, Note 13.
(23) ORION Research Instruction Manual, Residual Chlorine Electrode
Model 97-70, 1977. Method and price available from ORION Research
Incorporation, 840 Memorial Drive, Cambridge, Massachusetts 02138. Table
IB, Note 16.
(24) Bicinchoninate Method for Copper. Method 8506, Hach Handbook of
Water Analysis, 1979, Method and price available from Hach Chemical
Company, P.O. Box 300, Loveland, Colorado 80537. Table IB, Note 19.
(25) Hydrogen Ion (pH) Automated Electrode Method, Industrial Method
Number 378-75WA. October 1976. Bran & Luebbe (Technicon) Auto Analyzer
II. Method and price available from Bran & Luebbe Analyzing
Technologies, Inc. Elmsford, N.Y. 10523. Table IB, Note 21.
(26) 1,10-Phenanthroline Method using FerroVer Iron Reagent for
Water,
[[Page 52]]
Hach Method 8008, 1980. Method and price available from Hach Chemical
Company, P.O. Box 389 Loveland, Colorado 80537. Table IB, Note 22.
(27) Periodate Oxidation Method for Manganese, Method 8034, Hach
Handbook for Water Analysis, 1979. Method and price available from Hach
Chemical Company, P.O. Box 389, Loveland, Colorado 80537. Table IB, Note
23.
(28) Nitrogen, Nitrite--Low Range, Diazotization Method for Water
and Wastewater, Hach Method 8507, 1979. Method and price available from
Hach Chemical Company, P.O. Box 389, Loveland, Colorado 80537. Table IB,
Note 25.
(29) Zincon Method for Zinc, Method 8009. Hach Handbook for Water
Analysis, 1979. Method and price available from Hach Chemical Company,
P.O. Box 389, Loveland, Colorado 80537. Table IB, Note 33.
(30) ``Direct Determination of Elemental Phosphorus by Gas-Liquid
Chromatography,'' by R.F. Addison and R.G. Ackman, Journal of
Chromatography, Volume 47, No. 3, pp. 421-426, 1970. Available in most
public libraries. Back volumes of the Journal of Chromatography are
available from Elsevier/North-Holland, Inc., Journal Information Centre,
52 Vanderbilt Avenue, New York, NY 10164. Cost available from publisher.
Table IB, Note 28.
(31) ``Direct Current Plasma (DCP) Optical Emission Spectrometric
Method for Trace Elemental Analysis of Water and Wastes'', Method AES
0029, 1986-Revised 1991, Fison Instruments, Inc., 32 Commerce Center,
Cherry Hill Drive, Danvers, MA 01923. Table B, Note 34.
(32) ``Closed Vessel Microwave Digestion of Wastewater Samples for
Determination of Metals, CEM Corporation, P.O. Box 200, Matthews, North
Carolina 28106-0200, April 16, 1992. Available from the CEM Corporation.
Table IB, Note 36.
(33) ``Organochlorine Pesticides and PCBs in Wastewater Using Empore
\TM\ Disk'' Test Method 3M 0222, Revised 10/28/94. 3M Corporation, 3M
Center Building 220-9E-10, St. Paul, MN 55144-1000. Method available
from 3M Corporation. Table IC, Note 8 and Table ID, Note 8.
(34) USEPA. October 2002. Methods for Measuring the Acute Toxicity
of Effluents and Receiving Waters to Freshwater and Marine Organisms.
Fifth Edition. U.S. Environmental Protection Agency, Office of Water,
Washington, DC EPA 821-R-02-012. Available at http://www.epa.gov/
epahome/index/sources.htm or from National Technical Information
Service, 5285 Port Royal Road, Springfield, Virginia 22161, Pub. No.
PB2002-108488. Table IA, Note 25.
(35) ``Nitrogen, Total Kjeldahl, Method PAI-DK01 (Block Digestion,
Steam Distillation, Titrimetric Detection)'', revised 12/22/94.
Available from Perstorp Analytical Corporation, 9445 SW Ridder Rd.,
Suite 310, P.O. Box 648, Wilsonville, OK 97070. Table IB, Note 39.
(36) ``Nitrogen, Total Kjeldahl, Method PAI-DK02 (Block Digestion,
Steam Distillation, Colorimetric Detection)'', revised 12/22/94.
Available from Perstorp Analytical Corporation, 9445 SW Ridder Rd.,
Suite 310, P.O. Box 648, Wilsonville, OK 97070. Table IB, Note 40.
(37) ``Nitrogen, Total Kjeldahl, Method PAI-DK03 (Block Digestion,
Automated FIA Gas Diffusion)'', revised 12/22/94. Available from
Perstorp Analytical Corporation, 9445 SW Ridder Rd., Suite 310, P.O. Box
648, Wilsonville, OK 97070. Table IB, Note 41.
(38) USEPA. October 2002. Short-Term Methods for Measuring the
Chronic Toxicity of Effluents and Receiving Waters to Freshwater
Organisms. Fourth Edition. U.S. Environmental Protection Agency, Office
of Water, Washington, DC EPA 821-R-02-013. Available at http://
www.epa.gov/epahome/index/sources.htm or from National Technical
Information Service, 5285 Port Royal Road, Springfield, Virginia 22161,
Pub. No. PB2002-108489. Table IA, Note 26.
(39) USEPA. October 2002. Short-Term Methods for Measuring the
Chronic Toxicity of Effluents and Receiving Waters to Marine and
Estuarine Organisms. Third Edition. U.S. Environmental Protection
Agency, Office of Water, Washington, DC EPA 821-R-02-014. Available at
http://www.epa.gov/epahome/index/sources.htm or from National Technical
Information Service, 5285 Port Royal Road, Springfield, Virginia 22161,
Pub. No. PB2002-108490. Table IA, Note 27.
[[Page 53]]
(40) EPA Methods 1666, 1667, and 1671 listed in the table above are
published in the compendium titled Analytical Methods for the
Determination of Pollutants in Pharmaceutical Manufacturing Industry
Wastewaters (EPA 821-B-98-016). EPA Methods 502.2 and 524.2 have been
incorporated by reference into 40 CFR 141.24 and are in Methods for the
Determination of Organic Compounds in Drinking Water, EPA-600/4-88-039,
December 1988, Revised, July 1991, and Methods for the Determination of
Organic Compounds in Drinking Water-Supplement II, EPA-600/R-92-129,
August 1992, respectively. These EPA test method compendia are available
from the National Technical Information Service, NTIS PB91-231480 and
PB92-207703, U.S. Department of Commerce, 5285 Port Royal Road,
Springfield, Virginia 22161. The toll-free number is 800-553-6847. ASTM
test methods D3371, D3695, and D4763 are available from the American
Society for Testing and Materials, 100 Barr Harbor Drive, West
Conshohocken, PA 19428-2959.
(41) USEPA. 2002. Method 1631, Revision E, ``Mercury in Water by
Oxidation, Purge and Trap, and Cold Vapor Atomic Fluorescence
Spectrometry.'' September 2002. Office of Water, U.S. Environmental
Protection Agency (EPA-821-R-02-019). Available from: National Technical
Information Service, 5285 Port Royal Road, Springfield, Virginia 22161.
Publication No. PB2002-108220. Cost: $25.50 (subject to change).
(42) [Reserved]
(43) Method OIA-1677, Available Cyanide by Flow Injection, Ligand
Exchange, and Amperometry. August 1999. ALPKEM, OI Analytical, Box 648,
Wilsonville, Oregon 97070 (EPA-821-R-99-013). Available from: National
Technical Information Service, 5285 Port Royal Road, Springfield,
Virginia 22161. Publication No. PB99-132011. Cost: $22.50. Table IB,
Note 44.
(44) ``Methods of Analysis by the U.S. Geological Survey National
Water Quality Laboratory Determination of Ammonium Plus Organic Nitrogen
by a Kjeldahl Digestion Method and an Automated Photometric Finish that
Includes Digest Cleanup by Gas Diffusion'', Open File Report (OFR) 00-
170. Available from: U.S. Geological Survey, Denver Federal Center, Box
25425, Denver, CO 80225. Table IB, Note 45.
(45) ``Methods of Analysis by the U.S. Geological Survey National
Water Quality Laboratory--Determination of Chromium in Water by Graphite
Furnace Atomic Absorption Spectrophotometry'', Open File Report (OFR)
93-449. Available from: U.S. Geological Survey, Denver Federal Center,
Box 25425, Denver, CO 80225. Table IB, Note 46.
(46) ``Methods of Analysis by the U.S. Geological Survey National
Water Quality Laboratory--Determination of Molybdenum in Water by
Graphite Furnace Atomic Absorption Spectrophotometry'', Open File Report
(OFR) 97-198. Available from: U.S. Geological Survey, Denver Federal
Center, Box 25425, Denver, CO 80225. Table IB, Note 47.
(47) ``Methods of Analysis by the U.S. Geological Survey National
Water Quality Laboratory--Determination of Total Phosphorus by Kjeldahl
Digestion Method and an Automated Colorimetric Finish That Includes
Dialysis'' Open File Report (OFR) 92-146. Available from: U.S.
Geological Survey, Denver Federal Center, Box 25425, Denver, CO 80225.
Table IB, Note 48.
(48) ``Methods of Analysis by the U.S. Geological Survey National
Water Quality Laboratory--Determination of Arsenic and Selenium in Water
and Sediment by Graphite Furnace--Atomic Absorption Spectrometry'' Open
File Report (OFR) 98-639. Table IB, Note 49.
(49) ``Methods of Analysis by the U.S. Geological Survey National
Water Quality Laboratory--Determination of Elements in Whole-Water
Digests Using Inductively Coupled Plasma-Optical Emission Spectrometry
and Inductively Coupled Plasma-Mass Spectrometry'' , Open File Report
(OFR) 98-165. Available from: U.S. Geological Survey, Denver Federal
Center, Box 25425, Denver, CO 80225. Table IB, Note 50.
(50) ``Methods of Analysis by the U.S. Geological Survey National
Water Quality Laboratory--Determination of Triazine and Other Nitrogen-
containing Compounds by Gas Chromatography with Nitrogen Phosphorus
Detectors'' U.S.Geological Survey Open File Report 94-37. Available
from: U.S.
[[Page 54]]
Geological Survey, Denver Federal Center, Box 25425, Denver, CO 80225.
Table ID, Note 9.
(51) ``Methods of Analysis by the U.S. Geological Survey National
Water Quality Laboratory--Determination of Inorganic and Organic
Constituents in Water and Fluvial Sediments'', Open File Report (OFR)
93-125. Available from: U.S. Geological Survey, Denver Federal Center,
Box 25425, Denver, CO 80225. Table IB, Note 51; Table IC, Note 9.
(52) IDEXX Laboratories, Inc. 2002. Description of
Colilert[reg], Colilert-18[reg], Quanti-
Tray[reg], Quanti-Tray[reg]/2000,
Enterolert[reg] methods are available from IDEXX
Laboratories, Inc., One Idexx Drive, Westbrook, Maine 04092. Table IA,
Notes 17 and 23; Table IH, Notes 16 and 22.
(53) Hach Company, Inc. Revision 2, 1999. Description of m-
ColiBlue24[reg] Method, Total Coliforms and E. coli, is
available from Hach Company, 100 Dayton Ave, Ames IA 50010. Table IA,
Note 18; Table IH, Note 17.
(54) USEPA. July 2006. Method 1103.1: Escherichia coli (E. coli) in
Water by Membrane Filtration Using membrane-Thermotolerant Escherichia
coli Agar (mTEC). U.S. Environmental Protection Agency, Office of Water,
Washington DC EPA-621-R-06-010. Available at http://www.epa.gov/
waterscience/methods/. Table IH, Note 19.
(55) USEPA. July 2006. Method 1106.1: Enterococci in Water by
Membrane Filtration Using membrane-Enterococcus-Esculin Iron Agar (mE-
EIA). U.S. Environmental Protection Agency, Office of Water, Washington
DC EPA-621-R-06-008. Available at http://www.epa.gov/waterscience/
methods/. Table IH, Note 23
(56) USEPA. July 2006. Method 1603: Escherichia coli (E. coli) in
Water by Membrane Filtration Using Modified membrane-Thermotolerant
Escherichia coli Agar (Modified mTEC). U.S. Environmental Protection
Agency, Office of Water, Washington DC EPA-821-R-06-011. Available at
http://www.epa.gov/waterscience/methods/. Table IH, Note 19; Table IH,
Note 20.
(57) Brenner et al. 1993. New Medium for the Simultaneous Detection
of Total Coliforms and Escherichia coli in Water. Appl. Environ.
Microbiol. 59:3534-3544. Available from the American Society for
Microbiology, 1752 N Street NW., Washington DC 20036. Table IH, Note 21.
(58) USEPA. September 2002. Method 1604: Total Coliforms and
Escherichia coli (E. coli) in Water by Membrane Filtration Using a
Simultaneous Detection Technique (MI Medium). U.S. Environmental
Protection Agency, Office of Water, Washington DC EPA-821-R-02-024.
Available at http://www.epa.gov/waterscience/methods/. Table IH, Note
20.
(59) USEPA. July 2006. Method 1600: Enterococci in Water by Membrane
Filtration Using membrane-Enterococcus Indoxyl-[beta]-D-Glucoside Agar
(mEI). U.S. Environmental Protection Agency, Office of Water, Washington
DC EPA-821-R-06-009. Available at http://www.epa.gov/waterscience/
methods/. Table IA, Note 24; Table IH, Note 24.
(60) USEPA. April 2001. Method 1622: Cryptosporidium in Water by
Filtration/IMS/FA. U.S. Environmental Protection Agency, Office of
Water, Washington DC EPA-821-R-01-026. Available at http://www.epa.gov/
waterscience/methods/. Table IH, Note 25.
(61) USEPA. April 2001. Method 1623: Cryptosporidium and Giardia in
Water by Filtration/IMS/FA. U.S. Environmental Protection Agency, Office
of Water, Washington DC. EPA-821-R-01-025. Available at http://
www.epa.gov/waterscience/methods/. Table IH, Note 26.
(62) AOAC. 1995. Official Methods of Analysis of AOAC International,
16th Edition, Volume I, Chapter 17. AOAC International, 481 North
Frederick Avenue, Suite 500, Gaithersburg, Maryland 20877-2417. Table
IA, Note 11; Table IH.
(63) Waters Corporation. Method D6508, Rev. 2, ``Test Method for
Determination of Dissolved Inorganic Anions in Aqueous Matrices Using
Capillary Ion Electrophoresis and Chromate Electrolyte,'' available from
Waters Corp, 34 Maple Street, Milford, MA 01757, Telephone: 508/482-
2131, Fax: 508/482-3625, Table IB, See footnote 54.
(64) Kelada-01, ``Kelada Automated Test Methods for Total Cyanide,
Acid Dissociable Cyanide, and Thiocyanate,'' EPA 821-B-01-009 Revision
1.2, August 2001 is available from
[[Page 55]]
National Technical Information Service (NTIS), 5285 Port Royal Road,
Springfield, VA 22161 [Order Number PB 2001-108275]. Telephone: 800-553-
6847. Table IB, See footnote 55.
(65) QuikChem Method 10-204-00-1-X, ``Digestion and Distillation of
Total Cyanide in Drinking and Wastewaters using MICRO DIST and
Determination of Cyanide by Flow Injection Analysis'' Revision 2.2,
March 2005 is available from Lachat Instruments 6645 W. Mill Road,
Milwaukee, WI 53218, Telephone: 414-358-4200. Table IB, See footnote 56.
(66) ``Methods for the Determination of Metals in Environmental
Samples,'' Supplement I, National Exposure Risk Laboratory-Cincinnati
(NERL-CI), EPA/600/R-94/111, May 1994; and ``Methods for the
Determination of Inorganic Substances in Environmental Samples,'' NERL-
CI, EPA/600/R-93/100, August, 1993 are available from National Technical
Information Service (NTIS), 5285 Port Royal Road, Springfield, VA 22161.
Telephone: 800-553-6847. Table IB.
(67) ``Determination of Inorganic Ions in Drinking Water by Ion
Chromatography,'' Rev. 1.0, 1997 is available from from http://
www.epa.gov/safetwater/methods/met300.pdf. Table IB.
(68) Table IG Methods are available in ``Methods For The
Determination of Nonconventional Pesticides In Municipal and Industrial
Wastewater, Volume I,'' EPA 821-R-93-010A, August 1993 Revision I, and
``Methods For The Determination of Nonconventional Pesticides In
Municipal and Industrial Wastewater, Volume II,'' EPA 821-R-93-010B
(August 1993) are available from National Technical Information Service
(NTIS), 5285 Port Royal Road, Springfield, VA 22161. Telephone: 800-553-
6847.
(69) Method 245.7, Rev. 2.0, ``Mercury in Water by Cold Vapor Atomic
Fluorescence Spectrometry,'' February 2005, EPA-821-R-05-001, available
from the U.S. EPA Sample Control Center (operated by CSC), 6101
Stevenson Avenue, Alexandria, VA 22304, Telephone: 703-461-8056. Table
IB, See footnote 59.
(70) USEPA. July 2006. Method 1680: Fecal Coliforms in Sewage Sludge
(Biosolids) by Multiple-Tube Fermentation using Lauryl Tryptose Broth
(LTB) and EC Medium. U.S. Environmental Protection Agency, Office of
Water, Washington DC. EPA 821-R-06-012. Available at http://www.epa.gov/
waterscience/methods/.
(71) USEPA. July 2006. Method 1681: Fecal Coliforms in Sewage Sludge
(Biosolids) by Multiple-Tube Fermentation using A-1 Medium. U.S.
Environmental Protection Agency, Office of Water, Washington DC. EPA
821-R-06-013. Available at http://www.epa.gov/waterscience/methods/.
(72) USEPA. July 2006. Method 1682: Salmonella in Sewage Sludge
(Biosolids) by Modified Semisolid Rappaport-Vassiliadis (MSRV) Medium.
U.S. Environmental Protection Agency, Office of Water, Washington DC.
EPA 821-R-06-014. Available at http://www.epa.gov/waterscience/methods/.
(c) Under certain circumstances, the Regional Administrator or the
Director in the Region or State where the discharge will occur may
determine for a particular discharge that additional parameters or
pollutants must be reported. Under such circumstances, additional test
procedures for analysis of pollutants may be specified by the Regional
Administrator, or the Director upon recommendation of the Alternate Test
Procedure Program Coordinator, Washington, DC.
(d) Under certain circumstances, the Administrator may approve
additional alternate test procedures for nationwide use, upon
recommendation by the Alternate Test Procedure Program Coordinator,
Washington, DC.
(e) Sample preservation procedures, container materials, and maximum
allowable holding times for parameters are cited in Tables IA, IB, IC,
ID, IE, IF, IG and IH are prescribed in Table II. Information in the
table takes precedence over information in specific methods or
elsewhere. Any person may apply for a variance from the prescribed
preservation techniques, container materials, and maximum holding times
applicable to samples taken from a specific discharge. Applications for
variances may be made by letters to the Regional Administrator in the
Region in which the discharge will occur. Sufficient data should be
provided to assure such variance does not adversely affect the integrity
of the sample. Such data will be forwarded by
[[Page 56]]
the Regional Administrator, to the Alternate Test Procedure Program
Coordinator, Washington, DC, for technical review and recommendations
for action on the variance application. Upon receipt of the
recommendations from the Alternate Test Procedure Program Coordinator,
the Regional Administrator may grant a variance applicable to the
specific discharge to the applicant. A decision to approve or deny a
variance will be made within 90 days of receipt of the application by
the Regional Administrator.
Table II--Required Containers, Preservation Techniques, and Holding Times
----------------------------------------------------------------------------------------------------------------
Maximum holding time
Parameter No./name Container \1\ Preservation \2,3\ \4\
----------------------------------------------------------------------------------------------------------------
Table IA--Bacterial Tests:
1-5. Coliform, total, fecal, and PA, G.................. Cool, <10 [deg]C, 6 hours.\22,23\
E. coli. 0.0008% Na2S2O3 \5\.
6. Fecal streptococci............ PA, G.................. Cool, <10 [deg]C, 6 hours.\22\
0.0008% Na2S2O3 \5\.
7. Enterococci................... PA, G.................. Cool, <10 [deg]C, 6 hours.\22\
0.0008% Na2S2O3 \5\.
8. Salmonella.................... PA, G.................. Cool, <10 [deg]C, 6 hours.\22\
0.0008% Na2S2O3 \5\.
Table IA--Aquatic Toxicity Tests:
9-11. Toxicity, acute and chronic P, FP, G............... Cool, <=6 [deg]C \16\.. 36 hours.
Table lB--Inorganic Tests:
1. Acidity....................... P, FP, G............... Cool, <=6 [deg]C \18\.. 14 days.
2. Alkalinity.................... P, FP, G............... Cool, <=6 [deg]C \18\.. 14 days.
4. Ammonia....................... P, FP, G............... Cool, <=6 [deg]C \18\, 28 days.
H2SO4 to pH<2.
9. Biochemical oxygen demand..... P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
10. Boron........................ P, FP, or Quartz....... HNO3 to pH<2........... 6 months.
11. Bromide...................... P, FP, G............... None required.......... 28 days.
14. Biochemical oxygen demand, P, FP G................ Cool, <=6 [deg]C \18\.. 48 hours.
carbonaceous.
15. Chemical oxygen demand....... P, FP, G............... Cool, <=6 [deg]C \18\, 28 days.
H2SO4 to pH<2.
16. Chloride..................... P, FP, G............... None required.......... 28 days.
17. Chlorine, total residual..... P, G................... None required.......... Analyze within 15
minutes.
21. Color........................ P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
23-24. Cyanide, total or P, FP, G............... Cool, <=6 [deg]C \18\, 14 days.
available (or CATC). NaOH to pH12 \6\, reducing
agent \5\.
25. Fluoride..................... P...................... None required.......... 28 days.
27. Hardness..................... P, FP, G............... HNO3 or H2SO4 to pH<2.. 6 months.
28. Hydrogen ion (pH)............ P, FP, G............... None required.......... Analyze within 15
minutes.
31, 43. Kjeldahl and organic N... P, FP, G............... Cool, <=6 [deg]C \18\, 28 days.
H2SO4 to pH<2.
Table IB--Metals: \7\
18. Chromium VI.................. P, FP, G............... Cool, <=6 [deg]C \18\, 28 days.
pH = 9.3-9.7 \20\.
35. Mercury (CVAA)............... P, FP, G............... HNO3 to pH<2........... 28 days.
35. Mercury (CVAFS).............. FP, G; and FP-lined cap 5 mL/L 12N HCl or 5 mL/ 90 days.\17\
\17\. L BrCl \17\.
3, 5-8, 12, 13, 19, 20, 22, 26, P, FP, G............... HNO3 to pH<2, or at 6 months.
29, 30, 32-34, 36, 37, 45, 47, least 24 hours prior
51, 52, 58-60, 62, 63, 70-72, to analysis \19\.
74, 75.
Metals, except boron, chromium
VI, and mercury.
38. Nitrate...................... P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
39. Nitrate-nitrite.............. P, FP, G............... Cool, <=6 [deg]C \18\, 28 days.
H2SO4 to pH<2.
40. Nitrite...................... P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
41. Oil and grease............... G...................... Cool to <=6 [deg]C 28 days.
\18\, HCl or H2SO4 to
pH<2.
42. Organic Carbon............... P, FP, G............... Cool to <=6 [deg]C 28 days.
\18\, HCl, H2SO4, or
H3PO4 to pH<2.
44. Orthophosphate............... P, FP, G............... Cool, <=6 [deg]C \18\.. Filter within 15
minutes; Analyze
within 48 hours.
46. Oxygen, Dissolved Probe...... G, Bottle and top...... None required.......... Analyze within 15
minutes.
47. Winkler...................... G, Bottle and top...... Fix on site and store 8 hours.
in dark.
48. Phenols...................... G...................... Cool, <=6 [deg]C \18\, 28 days.
H2SO4 to pH<2.
49. Phosphorous (elemental)...... G...................... Cool, <=6 [deg]C \18\.. 48 hours.
50. Phosphorous, total........... P, FP, G............... Cool, <=6 [deg]C \18\, 28 days.
H2SO4 to pH<2.
53. Residue, total............... P, FP, G............... Cool, <=6 [deg]C \18\.. 7 days.
54. Residue, Filterable.......... P, FP, G............... Cool, <=6 [deg]C \18\.. 7 days.
55. Residue, Nonfilterable (TSS). P, FP, G............... Cool, <=6 [deg]C \18\.. 7 days.
56. Residue, Settleable.......... P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
[[Page 57]]
57. Residue, Volatile............ P, FP, G............... Cool, <=6 [deg]C \18\.. 7 days.
61. Silica....................... P or Quartz............ Cool, <=6 [deg]C \18\.. 28 days.
64. Specific conductance......... P, FP, G............... Cool, <=6 [deg]C \18\.. 28 days.
65. Sulfate...................... P, FP, G............... Cool, <=6 [deg]C \18\.. 28 days.
66. Sulfide...................... P, FP, G............... Cool, <=6 [deg]C \18\, 7 days.
add zinc acetate plus
sodium hydroxide to
pH9.
67. Sulfite...................... P, FP, G............... None required.......... Analyze within 15
minutes.
68. Surfactants.................. P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
69. Temperature.................. P, FP, G............... None required.......... Analyze.
73. Turbidity.................... P, FP, G............... Cool, <=6 [deg]C \18\.. 48 hours.
Table lC--Organic Tests \8\
13, 18-20, 22, 24-28, 34-37, 39- G, FP-lined septum..... Cool, <=6 [deg]C \18\, 14 days.
43, 45-47, 56, 76, 104, 105, 108- 0.008% Na2S2O3 \5\.
111, 113. Purgeable Halocarbons.
6, 57, 106. Purgeable aromatic G, FP-lined septum..... Cool, <=6 [deg]C \18\, 14 days.\9\
hydrocarbons. 0.008% Na2S2O3 \5\,
HCl to pH 2 \9\.
3, 4. Acrolein and acrylonitrile. G, FP-lined septum..... Cool, <=6 [deg]C \18\, 14 days.\10\
0.008% Na2S2O3 \5\, pH
to 4-5 \10\.
23, 30, 44, 49, 53, 77, 80, 81, G, FP-lined cap........ Cool, <=6 [deg]C \18\, 7 days until
98, 100, 112. Phenols \11\. 0.008% Na2S2O3 \5\. extraction, 40 days
after extraction.
7, 38. Benzidines \11,12\........ G, FP-lined cap........ Cool, <=6 [deg]C \18\, 7 days until
0.008% Na2S2O3 \5\. extraction.\13\
14, 17, 48, 50-52. Phthalate G, FP-lined cap........ Cool, <=6 [deg]C \18\.. 7 days until
esters \11\. extraction, 40 days
after extraction.
82-84. Nitrosamines \11,14\...... G, FP-lined cap........ Cool, <=6 [deg]C \18\, 7 days until
store in dark, 0.008% extraction, 40 days
Na2S2O3 \5\. after extraction.
88-94. PCBs \11\................. G, FP-lined cap........ Cool, <=6 [deg]C \18\.. 1 year until
extraction, 1 year
after extraction.
54, 55, 75, 79. Nitroaromatics G, FP-lined cap........ Cool, <=6 [deg]C \18\, 7 days until
and isophorone \11\. store in dark, 0.008% extraction, 40 days
Na2S2O3 \5\. after extraction.
1, 2, 5, 8-12, 32, 33, 58, 59, G, FP-lined cap........ Cool, <=6 [deg]C \18\, 7 days until
74, 78, 99, 101. Polynuclear store in dark, 0.008% extraction, 40 days
aromatic hydrocarbons \11\. Na2S2O3 \5\. after extraction.
15, 16, 21, 31, 87. Haloethers G, FP-lined cap........ Cool, <=6 [deg]C \18\, 7 days until
\11\. 0.008% Na2S2O3 \5\. extraction, 40 days
after extraction.
29, 35-37, 63-65, 107. G, FP-lined cap........ Cool, <=6 [deg]C \18\.. 7 days until
Chlorinated hydrocarbons \11\. extraction, 40 days
after extraction.
60-62, 66-72, 85, 86, 95-97, 102,
103. CDDs/CDFs \11\.
Aqueous Samples: Field and Lab G...................... Cool, <=6 [deg]C \18\, 1 year.
Preservation. 0.008% Na2S2O3 \5\,
pH<9.
Solids and Mixed-Phase Samples: G...................... Cool, <=6 [deg]C \18\.. 7 days.
Field Preservation.
Tissue Samples: Field G...................... Cool, <=6 [deg]C \18\.. 24 hours.
Preservation.
Solids, Mixed-Phase, and Tissue G...................... Freeze, <=-10 [deg]C... 1 year.
Samples: Lab Preservation.
Table lD--Pesticides Tests:
1-70. Pesticides \11\............ G, FP-lined cap........ Cool, <=6 [deg]C \18\, 7 days until
pH 5-9 \15\. extraction, 40 days
after extraction.
Table IE--Radiological Tests:
1-5. Alpha, beta, and radium..... P, FP, G............... HNO3 to pH<2........... 6 months.
Table IH--Bacterial Tests:
1. E. coli....................... PA, G.................. Cool, <10 [deg]C, 6 hours.\22\
0.0008% Na2S2O3 \5\.
2. Enterococci................... PA, G.................. Cool, <10 [deg]C, 6 hours.\22\
0.0008% Na2S2O3 \5\.
Table IH--Protozoan Tests:
8. Cryptosporidium............... LDPE; field filtration. 0-8 [deg]C............. 96 hours.\21\
[[Page 58]]
9. Giardia....................... LDPE; field filtration. 0-8 [deg]C............. 96 hours.\21\
----------------------------------------------------------------------------------------------------------------
\1\ ``P'' is polyethylene; ``FP'' is fluoropolymer (polytetrafluoroethylene (PTFE; Teflon[reg]), or other
fluoropolymer, unless stated otherwise in this Table II; ``G'' is glass; ``PA'' is any plastic that is made of
a sterlizable material (polypropylene or other autoclavable plastic); ``LDPE'' is low density polyethylene.
\2\ Except where noted in this Table II and the method for the parameter, preserve each grab sample within 15
minutes of collection. For a composite sample collected with an automated sampler (e.g., using a 24-hour
composite sampler; see 40 CFR 122.21(g)(7)(i) or 40 CFR part 403, Appendix E), refrigerate the sample at <=6
[deg]C during collection unless specified otherwise in this Table II or in the method(s). For a composite
sample to be split into separate aliquots for preservation and/or analysis, maintain the sample at <=6 [deg]C,
unless specified otherwise in this Table II or in the method(s), until collection, splitting, and preservation
is completed. Add the preservative to the sample container prior to sample collection when the preservative
will not compromise the integrity of a grab sample, a composite sample, or an aliquot split from a composite
sample; otherwise, preserve the grab sample, composite sample, or aliquot split from a composite sample within
15 minutes of collection. If a composite measurement is required but a composite sample would compromise
sample integrity, individual grab samples must be collected at prescribed time intervals (e.g., 4 samples over
the course of a day, at 6-hour intervals). Grab samples must be analyzed separately and the concentrations
averaged. Alternatively, grab samples may be collected in the field and composited in the laboratory if the
compositing procedure produces results equivalent to results produced by arithmetic averaging of the results
of analysis of individual grab samples. For examples of laboratory compositing procedures, see EPA Method
1664A (oil and grease) and the procedures at 40 CFR 141.34(f)(14)(iv) and (v) (volatile organics).
\3\ When any sample is to be shipped by common carrier or sent via the U.S. Postal Service, it must comply with
the Department of Transportation Hazardous Materials Regulations (49 CFR part 172). The person offering such
material for transportation is responsible for ensuring such compliance. For the preservation requirements of
Table II, the Office of Hazardous Materials, Materials Transportation Bureau, Department of Transportation has
determined that the Hazardous Materials Regulations do not apply to the following materials: Hydrochloric acid
(HCl) in water solutions at concentrations of 0.04% by weight or less (pH about 1.96 or greater); Nitric acid
(HNO3) in water solutions at concentrations of 0.15% by weight or less (pH about 1.62 or greater); Sulfuric
acid (H2SO4) in water solutions at concentrations of 0.35% by weight or less (pH about 1.15 or greater); and
Sodium hydroxide (NaOH) in water solutions at concentrations of 0.080% by weight or less (pH about 12.30 or
less).
\4\ Samples should be analyzed as soon as possible after collection. The times listed are the maximum times that
samples may be held before the start of analysis and still be considered valid (e.g., samples analyzed for
fecal coliforms may be held up to 6 hours prior to commencing analysis). Samples may be held for longer
periods only if the permittee or monitoring laboratory has data on file to show that, for the specific types
of samples under study, the analytes are stable for the longer time, and has received a variance from the
Regional Administrator under Sec. 136.3(e). For a grab sample, the holding time begins at the time of
collection. For a composite sample collected with an automated sampler (e.g., using a 24-hour composite
sampler; see 40 CFR 122.21(g)(7)(i) or 40 CFR part 403, Appendix E), the holding time begins at the time of
the end of collection of the composite sample. For a set of grab samples composited in the field or
laboratory, the holding time begins at the time of collection of the last grab sample in the set. Some samples
may not be stable for the maximum time period given in the table. A permittee or monitoring laboratory is
obligated to hold the sample for a shorter time if it knows that a shorter time is necessary to maintain
sample stability. See Sec. 136.3(e) for details. The date and time of collection of an individual grab
sample is the date and time at which the sample is collected. For a set of grab samples to be composited, and
that are all collected on the same calendar date, the date of collection is the date on which the samples are
collected. For a set of grab samples to be composited, and that are collected across two calendar dates, the
date of collection is the dates of the two days; e.g., November 14-15. For a composite sample collected
automatically on a given date, the date of collection is the date on which the sample is collected. For a
composite sample collected automatically, and that is collected across two calendar dates, the date of
collection is the dates of the two days; e.g., November 14-15.
\5\ Add a reducing agent only if an oxidant (e.g., chlorine) is present. Reducing agents shown to be effective
are sodium thiosulfate (Na2S2O3), ascorbic acid, sodium arsenite (NaAsO2), or sodium borohydride (NaBH4).
However, some of these agents have been shown to produce a positive or negative cyanide bias, depending on
other substances in the sample and the analytical method used. Therefore, do not add an excess of reducing
agent. Methods recommending ascorbic acid (e.g., EPA Method 335.4) specify adding ascorbic acid crystals, 0.1-
0.6 g, until a drop of sample produces no color on potassium iodide (KI) starch paper, then adding 0.06 g (60
mg) for each liter of sample volume. If NaBH4 or NaAsO2 is used, 25 mg/L NaBH4 or 100 mg/L NaAsO2 will reduce
more than 50 mg/L of chlorine (see method ``Kelada-01'' and/or Standard Method 4500-CN- for more information).
After adding reducing agent, test the sample using KI paper, a test strip (e.g. for chlorine, SenSafe\TM\
Total Chlorine Water Check 480010) moistened with acetate buffer solution (see Standard Method 4500-Cl.C.3e),
or a chlorine/oxidant test method (e.g., EPA Method 330.4 or 330.5), to make sure all oxidant is removed. If
oxidant remains, add more reducing agent. Whatever agent is used, it should be tested to assure that cyanide
results are not affected adversely.
\6\ Sample collection and preservation: Collect a volume of sample appropriate to the analytical method in a
bottle of the material specified. If the sample can be analyzed within 48 hours and sulfide is not present,
adjust the pH to 12 with sodium hydroxide solution (e.g., 5% w/v), refrigerate as specified, and
analyze within 48 hours. Otherwise, to extend the holding time to 14 days and mitigate interferences, treat
the sample immediately using any or all of the following techniques, as necessary, followed by adjustment of
the sample pH to 12 and refrigeration as specified. There may be interferences that are not
mitigated by approved procedures. Any procedure for removal or suppression of an interference may be employed,
provided the laboratory demonstrates that it more accurately measures cyanide. Particulate cyanide (e.g.,
ferric ferrocyanide) or a strong cyanide complex (e.g., cobalt cyanide) are more accurately measured if the
laboratory holds the sample at room temperature and pH 12 for a minimum of 4 hours prior to
analysis, and performs UV digestion or dissolution under alkaline (pH=12) conditions, if necessary.
(1) Sulfur: To remove elemental sulfur (S8), filter the sample immediately. If the filtration time will exceed
15 minutes, use a larger filter or a method that requires a smaller sample volume (e.g., EPA Method 335.4 or
Lachat Method 01). Adjust the pH of the filtrate to > 12 with NaOH, refrigerate the filter and filtrate, and
ship or transport to the laboratory. In the laboratory, extract the filter with 100 mL of 5% NaOH solution for
a minimum of 2 hours. Filter the extract and discard the solids. Combine the 5% NaOH-extracted filtrate with
the initial filtrate, lower the pH to approximately 12 with concentrated hydrochloric or sulfuric acid, and
analyze the combined filtrate. Because the detection limit for cyanide will be increased by dilution by the
filtrate from the solids, test the sample with and without the solids procedure if a low detection limit for
cyanide is necessary. Do not use the solids procedure if a higher cyanide concentration is obtained without
it. Alternatively, analyze the filtrates from the sample and the solids separately, add the amounts determined
(in [mu]g or mg), and divide by the original sample volume to obtain the cyanide concentration.
[[Page 59]]
(2) Sulfide: If the sample contains sulfide as determined by lead acetate paper, or if sulfide is known or
suspected to be present, immediately conduct one of the volatilization treatments or the precipitation
treatment as follows: Volatilization--Headspace expelling. In a fume hood or well-ventilated area, transfer
0.75 liter of sample to a 4.4 L collapsible container (e.g., Cubitainer\TM\). Acidify with concentrated
hydrochloric acid to pH < 2. Cap the container and shake vigorously for 30 seconds. Remove the cap and expel
the headspace into the fume hood or open area by collapsing the container without expelling the sample. Refill
the headspace by expanding the container. Repeat expelling a total of five headspace volumes. Adjust the pH to
12, refrigerate, and ship or transport to the laboratory. Scaling to a smaller or larger sample
volume must maintain the air to sample volume ratio. A larger volume of air will result in too great a loss of
cyanide ( 10%). Dynamic stripping: In a fume hood or well-ventilated area, transfer 0.75 liter of
sample to a container of the material specified and acidify with concentrated hydrochloric acid to pH < 2.
Using a calibrated air sampling pump or flowmeter, purge the acidified sample into the fume hood or open area
through a fritted glass aerator at a flow rate of 2.25 L/min for 4 minutes. Adjust the pH to 12,
refrigerate, and ship or transport to the laboratory. Scaling to a smaller or larger sample volume must
maintain the air to sample volume ratio. A larger volume of air will result in too great a loss of cyanide
( 10%). Precipitation: If the sample contains particulate matter that would be removed by
filtration, filter the sample prior to treatment to assure that cyanide associated with the particulate matter
is included in the measurement. Ship or transport the filter to the laboratory. In the laboratory, extract the
filter with 100 mL of 5% NaOH solution for a minimum of 2 hours. Filter the extract and discard the solids.
Combine the 5% NaOH-extracted filtrate with the initial filtrate, lower the pH to approximately 12 with
concentrated hydrochloric or sulfuric acid, and analyze the combined filtrate. Because the detection limit for
cyanide will be increased by dilution by the filtrate from the solids, test the sample with and without the
solids procedure if a low detection limit for cyanide is necessary. Do not use the solids procedure if a
higher cyanide concentration is obtained without it. Alternatively, analyze the filtrates from the sample and
the solids separately, add the amounts determined (in [mu]g or mg), and divide by the original sample volume
to obtain the cyanide concentration. For removal of sulfide by precipitation, raise the pH of the sample to
12 with NaOH solution, then add approximately 1 mg of powdered cadmium chloride for each mL of
sample. For example, add approximately 500 mg to a 500-mL sample. Cap and shake the container to mix. Allow
the precipitate to settle and test the sample with lead acetate paper. If necessary, add cadmium chloride but
avoid adding an excess. Finally, filter through 0.45 micron filter. Cool the sample as specified and ship or
transport the filtrate and filter to the laboratory. In the laboratory, extract the filter with 100 mL of 5%
NaOH solution for a minimum of 2 hours. Filter the extract and discard the solids. Combine the 5% NaOH-
extracted filtrate with the initial filtrate, lower the pH to approximately 12 with concentrated hydrochloric
or sulfuric acid, and analyze the combined filtrate. Because the detection limit for cyanide will be increased
by dilution by the filtrate from the solids, test the sample with and without the solids procedure if a low
detection limit for cyanide is necessary. Do not use the solids procedure if a higher cyanide concentration is
obtained without it. Alternatively, analyze the filtrates from the sample and the solids separately, add the
amounts determined (in [mu]g or mg), and divide by the original sample volume to obtain the cyanide
concentration. If a ligand-exchange method is used (e.g., ASTM D6888), it may be necessary to increase the
ligand-exchange reagent to offset any excess of cadmium chloride.
(3) Sulfite, thiosulfate, or thiocyanate: If sulfite, thiosulfate, or thiocyanate is known or suspected to be
present, use UV digestion with a glass coil (Method Kelada-01) or ligand exchange (Method OIA-1677) to
preclude cyanide loss or positive interference.
(4) Aldehyde: If formaldehyde, acetaldehyde, or another water-soluble aldehyde is known or suspected to be
present, treat the sample with 20 mL of 3.5% ethylenediamine solution per liter of sample.
(5) Carbonate: Carbonate interference is evidenced by noticeable effervescence upon acidification in the
distillation flask, a reduction in the pH of the absorber solution, and incomplete cyanide spike recovery.
When significant carbonate is present, adjust the pH to =12 using calcium hydroxide instead of
sodium hydroxide. Allow the precipitate to settle and decant or filter the sample prior to analysis (also see
Standard Method 4500-CN.B.3.d).
(6) Chlorine, hypochlorite, or other oxidant: Treat a sample known or suspected to contain chlorine,
hypochlorite, or other oxidant as directed in footnote 5.
\7\ For dissolved metals, filter grab samples within 15 minutes of collection and before adding preservatives.
For a composite sample collected with an automated sampler (e.g., using a 24-hour composite sampler; see 40
CFR 122.21(g)(7)(i) or 40 CFR part 403, appendix E), filter the sample within 15 minutes after completion of
collection and before adding preservatives. If it is known or suspected that dissolved sample integrity will
be compromised during collection of a composite sample collected automatically over time (e.g., by interchange
of a metal between dissolved and suspended forms), collect and filter grab samples to be composited (footnote
2) in place of a composite sample collected automatically.
\8\ Guidance applies to samples to be analyzed by GC, LC, or GC/MS for specific compounds.
\9\ If the sample is not adjusted to pH 2, then the sample must be analyzed within seven days of sampling.
\10\ The pH adjustment is not required if acrolein will not be measured. Samples for acrolein receiving no pH
adjustment must be analyzed within 3 days of sampling.
\11\ When the extractable analytes of concern fall within a single chemical category, the specified preservative
and maximum holding times should be observed for optimum safeguard of sample integrity (i.e., use all
necessary preservatives and hold for the shortest time listed). When the analytes of concern fall within two
or more chemical categories, the sample may be preserved by cooling to <=6 [deg]C, reducing residual chlorine
with 0.008% sodium thiosulfate, storing in the dark, and adjusting the pH to 6-9; samples preserved in this
manner may be held for seven days before extraction and for forty days after extraction. Exceptions to this
optional preservation and holding time procedure are noted in footnote 5 (regarding the requirement for
thiosulfate reduction), and footnotes 12, 13 (regarding the analysis of benzidine).
\12\ If 1,2-diphenylhydrazine is likely to be present, adjust the pH of the sample to 4.0
0.2 to prevent rearrangement to benzidine.
\13\ Extracts may be stored up to 30 days at < 0 [deg]C.
\14\ For the analysis of diphenylnitrosamine, add 0.008% Na2S2O3 and adjust pH to 7-10 with NaOH within 24 hours
of sampling.
\15\ The pH adjustment may be performed upon receipt at the laboratory and may be omitted if the samples are
extracted within 72 hours of collection. For the analysis of aldrin, add 0.008% Na2S2O3.
\16\ Sufficient ice should be placed with the samples in the shipping container to ensure that ice is still
present when the samples arrive at the laboratory. However, even if ice is present when the samples arrive, it
is necessary to immediately measure the temperature of the samples and confirm that the preservation
temperature maximum has not been exceeded. In the isolated cases where it can be documented that this holding
temperature cannot be met, the permittee can be given the option of on-site testing or can request a variance.
The request for a variance should include supportive data which show that the toxicity of the effluent samples
is not reduced because of the increased holding temperature.
\17\ Samples collected for the determination of trace level mercury (<100 ng/L) using EPA Method 1631 must be
collected in tightly-capped fluoropolymer or glass bottles and preserved with BrCl or HCl solution within 48
hours of sample collection. The time to preservation may be extended to 28 days if a sample is oxidized in the
sample bottle. A sample collected for dissolved trace level mercury should be filtered in the laboratory
within 24 hours of the time of collection. However, if circumstances preclude overnight shipment, the sample
should be filtered in a designated clean area in the field in accordance with procedures given in Method 1669.
If sample integrity will not be maintained by shipment to and filtration in the laboratory, the sample must be
filtered in a designated clean area in the field within the time period necessary to maintain sample
integrity. A sample that has been collected for determination of total or dissolved trace level mercury must
be analyzed within 90 days of sample collection.
\18\ Aqueous samples must be preserved at <=6 [deg]C, and should not be frozen unless data demonstrating that
sample freezing does not adversely impact sample integrity is maintained on file and accepted as valid by the
regulatory authority. Also, for purposes of NPDES monitoring, the specification of ``<= [deg]C'' is used in
place of the ``4 [deg]C'' and ``< 4 [deg]C'' sample temperature requirements listed in some methods. It is not
necessary to measure the sample temperature to three significant figures (\1/100\th of 1 degree); rather,
three significant figures are specified so that rounding down to 6 [deg]C may not be used to meet the <=6
[deg]C requirement. The preservation temperature does not apply to samples that are analyzed immediately (less
than 15 minutes).
[[Page 60]]
\19\ An aqueous sample may be collected and shipped without acid preservation. However, acid must be added at
least 24 hours before analysis to dissolve any metals that adsorb to the container walls. If the sample must
be analyzed within 24 hours of collection, add the acid immediately (see footnote 2). Soil and sediment
samples do not need to be preserved with acid. The allowances in this footnote supersede the preservation and
holding time requirements in the approved metals methods.
\20\ To achieve the 28-day holding time, use the ammonium sulfate buffer solution specified in EPA Method 218.6.
The allowance in this footnote supersedes preservation and holding time requirements in the approved
hexavalent chromium methods, unless this supersession would compromise the measurement, in which case
requirements in the method must be followed.
\21\ Holding time is calculated from time of sample collection to elution for samples shipped to the laboratory
in bulk and calculated from the time of sample filtration to elution for samples filtered in the field.
\22\ Samples analysis should begin immediately, preferably within 2 hours of collection. The maximum transport
time to the laboratory is 6 hours, and samples should be processed within 2 hours of receipt at the
laboratory.
\23\ For fecal coliform samples for sewage sludge (biosolids) only, the holding time is extended to 24 hours for
the following sample types using either EPA Method 1680 (LTB-EC) or 1681 (A-1): Class A composted, Class B
aerobically digested, and Class B anaerobically digested.
[38 FR 28758, Oct. 16, 1973]
Editorial Note: For Federal Register citations affecting Sec.
136.3, see the List of CFR Sections Affected, which appears in the
Finding Aids section of the printed volume and on GPO Access.
Sec. 136.4 Application for alternate test procedures.
(a) Any person may apply to the Regional Administrator in the Region
where the discharge occurs for approval of an alternative test
procedure.
(b) When the discharge for which an alternative test procedure is
proposed occurs within a State having a permit program approved pursuant
to section 402 of the Act, the applicant shall submit his application to
the Regional Administrator through the Director of the State agency
having responsibility for issuance of NPDES permits within such State.
(c) Unless and until printed application forms are made available,
an application for an alternate test procedure may be made by letter in
triplicate. Any application for an alternate test procedure under this
paragraph (c) shall:
(1) Provide the name and address of the responsible person or firm
making the discharge (if not the applicant) and the applicable ID number
of the existing or pending permit, issuing agency, and type of permit
for which the alternate test procedure is requested, and the discharge
serial number.
(2) Identify the pollutant or parameter for which approval of an
alternate testing procedure is being requested.
(3) Provide justification for using testing procedures other than
those specified in Table I.
(4) Provide a detailed description of the proposed alternate test
procedure, together with references to published studies of the
applicability of the alternate test procedure to the effluents in
question.
(d) An application for approval of an alternate test procedure for
nationwide use may be made by letter in triplicate to the Alternate Test
Procedure Program Coordinator, Office of Science and Technology (4303),
Office of Water, U.S. Environmental Protection Agency, 1200 Pennsylvania
Ave., NW., Washington, DC 20460. Any application for an alternate test
procedure under this paragraph (d) shall:
(1) Provide the name and address of the responsible person or firm
making the application.
(2) Identify the pollutant(s) or parameter(s) for which nationwide
approval of an alternate testing procedure is being requested.
(3) Provide a detailed description of the proposed alternate
procedure, together with references to published or other studies
confirming the general applicability of the alternate test procedure to
the pollutant(s) or parameter(s) in waste water discharges from
representative and specified industrial or other categories.
(4) Provide comparability data for the performance of the proposed
alternate test procedure compared to the performance of the approved
test procedures.
[38 FR 28760, Oct. 16, 1973, as amended at 41 FR 52785, Dec. 1, 1976; 62
FR 30763, June 5, 1997; 72 FR 11239, Mar. 12, 2007]
Sec. 136.5 Approval of alternate test procedures.
(a) The Regional Administrator of the region in which the discharge
will
[[Page 61]]
occur has final responsibility for approval of any alternate test
procedure proposed by the responsible person or firm making the
discharge.
(b) Within thirty days of receipt of an application, the Director
will forward such application proposed by the responsible person or firm
making the discharge, together with his recommendations, to the Regional
Administrator. Where the Director recommends rejection of the
application for scientific and technical reasons which he provides, the
Regional Administrator shall deny the application and shall forward this
decision to the Director of the State Permit Program and to the
Alternate Test Procedure Program Coordinator, Office of Science and
Technology (4303), Office of Water, U.S. Environmental Protection
Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
(c) Before approving any application for an alternate test procedure
proposed by the responsible person or firm making the discharge, the
Regional Administrator shall forward a copy of the application to the
Alternate Test Procedure Program Coordinator, Office of Science and
Technology (4303), Office of Water, U.S. Environmental Protection
Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
(d) Within ninety days of receipt by the Regional Administrator of
an application for an alternate test procedure, proposed by the
responsible person or firm making the discharge, the Regional
Administrator shall notify the applicant and the appropriate State
agency of approval or rejection, or shall specify the additional
information which is required to determine whether to approve the
proposed test procedure. Prior to the expiration of such ninety day
period, a recommendation providing the scientific and other technical
basis for acceptance or rejection will be forwarded to the Regional
Administrator by the Alternate Test Procedure Program Coordinator,
Washington, DC. A copy of all approval and rejection notifications will
be forwarded to the Alternate Test Procedure Program Coordinator, Office
of Science and Technology (4303), Office of Water, U.S. Environmental
Protection Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460,
for the purposes of national coordination.
(e) Approval for nationwide use. (1) As expeditiously as is
practicable after receipt by the Alternate Test Procedure Program
Coordinator, Washington, DC, of an application for an alternate test
procedure for nationwide use, the Alternate Test Procedure Program
Coordinator, Washington, DC, shall notify the applicant in writing
whether the application is complete. If the application is incomplete,
the applicant shall be informed of the information necessary to make the
application complete.
(2) As expeditiously as is practicable after receipt of a complete
package, the Alternate Test Procedure Program Coordinator shall perform
any analysis necessary to determine whether the alternate test procedure
satisfies the applicable requirements of this part, and the Alternate
Test Procedure Program Coordinator shall recommend to the Administrator
that he/she approve or reject the application and shall also notify the
application of the recommendation.
(3) As expeditiously as practicable, an alternate method determined
by the Administrator to satisfy the applicable requirements of this part
shall be proposed by EPA for incorporation in subsection 136.3 of 40 CFR
part 136. EPA shall make available for review all the factual bases for
its proposal, including any performance data submitted by the applicant
and any available EPA analysis of those data.
(4) Following a period of public comment, EPA shall, as
expeditiously as practicable, publish in the Federal Register a final
decision to approve or reject the alternate method.
[38 FR 28760, Oct. 16, 1973, as amended at 41 FR 52785, Dec. 1, 1976; 55
FR 33440, Aug. 15, 1990; 62 FR 30763, June 5, 1997; 72 FR 11239, Mar.
12, 2007]
Sec. 136.6 Method modifications and analytical requirements.
(a) Definitions of terms used in this section.
(1) Analyst means the person or laboratory using a test procedure
(analytical method) in this Part.
(2) Chemistry of the method means the reagents and reactions used in
a test
[[Page 62]]
procedure that allow determination of the analyte(s) of interest in an
environmental sample.
(3) Determinative technique means the way in which an analyte is
identified and quantified (e.g., colorimetry, mass spectrometry).
(4) Equivalent Performance means that the modified method produces
results that meet the QC acceptance criteria of the approved method at
this part.
(5) Method-defined analyte means an analyte defined solely by the
method used to determine the analyte. Such an analyte may be a physical
parameter, a parameter that is not a specific chemical, or a parameter
that may be comprised of a number of substances. Examples of such
analytes include temperature, oil and grease, total suspended solids,
total phenolics, turbidity, chemical oxygen demand, and biochemical
oxygen demand.
(6) QC means ``quality control.''
(b) Method modifications--(1) Allowable changes. Except as set forth
in paragraph (b)(3) of this section, an analyst may modify an approved
test procedure (analytical method) provided that the chemistry of the
method or the determinative technique is not changed, and provided that
the requirements of paragraph (b)(2) of this section are met.
(i) Potentially acceptable modifications regardless of current
method performance include changes between automated and manual discrete
instrumentation; changes in the calibration range (provided that the
modified range covers any relevant regulatory limit); changes in
equipment such as using similar equipment from a vendor other than that
mentioned in the method (e.g., a purge-and-trap device from OIA rather
than Tekmar), changes in equipment operating parameters such as changing
the monitoring wavelength of a colorimeter or modifying the temperature
program for a specific GC column; changes to chromatographic columns
(treated in greater detail in paragraph (d) of this section); and
increases in purge-and-trap sample volumes (provided specifications in
paragraph (e) of this section are met). The changes are only allowed
provided that all the requirements of paragraph (b)(2) of this section
are met.
(ii) If the characteristics of a wastewater matrix prevent efficient
recovery of organic pollutants and prevent the method from meeting QC
requirements, the analyst may attempt to resolve the issue by using
salts as specified in Guidance on Evaluation, Resolution, and
Documentation of Analytical Problems Associated with Compliance
Monitoring (EPA 821-B-93-001, June 1993), provided that such salts do
not react with or introduce the target pollutant into the sample (as
evidenced by the analysis of method blanks, laboratory control samples,
and spiked samples that also contain such salts) and that all
requirements of paragraph (b)(2) of this section are met. Chlorinated
samples must be dechlorinated prior to the addition of such salts.
(iii) If the characteristics of a wastewater matrix result in poor
sample dispersion or reagent deposition on equipment and prevents the
analyst from meeting QC requirements, the analysts may attempt to
resolve the issue by adding an inert surfactant (i.e. a surfactant that
will not affect the chemistry of the method), which may include Brij-35
or sodium dodecyl sulfate (SDS), provided that such surfactant does not
react with or introduce the target pollutant into the sample (as
evidenced by the analysis of method blanks, laboratory control samples,
and spiked samples that also contain such surfactant) and that all
requirements of paragraph (b)(2) of this section are met. Chlorinated
samples must be dechlorinated prior to the addition of such surfactant.
(2) Requirements. A modified method must produce equivalent
performance to the approved methods for the analyte(s) of interest, and
the equivalent performance must be documented.
(i) Requirements for establishing equivalent performance
(A) If the approved method contains QC tests and QC acceptance
criteria, the modified method must use these QC tests and the modified
method must meet the QC acceptance criteria. The Analyst may only rely
on QC tests and QC acceptance criteria in a method if it includes
wastewater matrix QC tests and QC acceptance criteria (e.g., as matrix
spikes) and both initial (start-up)
[[Page 63]]
and ongoing QC tests and QC acceptance criteria.
(B) If the approved method does not contain QC tests and QC
acceptance criteria, or if the QC tests and QC acceptance criteria in
the method do not meet the requirements of paragraph (b)(2)(i)(A) of
this section, the analyst must employ QC tests specified in Protocol for
EPA Approval of Alternate Test Procedures for Organic and Inorganic
Analytes in Wastewater and Drinking Water (EPA-821-B-98-002, March 1999)
and meet the QC provisions specified therein. In addition, the Analyst
must perform on-going QC tests, including assessment of performance of
the modified method on the sample matrix (e.g., analysis of a matrix
spike/matrix spike duplicate pair for every twenty samples of a
discharge analyzed), and analysis of an ongoing precision and recovery
sample and a blank with each batch of 20 or fewer samples.
(C) Calibration must be performed using the modified method and the
modified method must be tested with every wastewater matrix to which it
will be applied (up to nine distinct matrices; as described in the ATP
Protocol, after validation in nine distinct matrices, the method may be
applied to all wastewater matrices), in addition to any and all reagent
water tests. If the performance in the wastewater matrix or reagent
water does not meet the QC acceptance criteria the method modification
may not be used.
(D) Analysts must test representative effluents with the modified
method, and demonstrate that the results are equivalent or superior to
results with the unmodified method.
(ii) Requirements for documentation. The modified method must be
documented in a method write-up or an addendum that describes the
modification(s) to the approved method. The write-up or addendum must
include a reference number (e.g., method number), revision number, and
revision date so that it may be referenced accurately. In addition, the
organization that uses the modified method must document the results of
QC tests and keep these records, along with a copy of the method write-
up or addendum, for review by an auditor.
(3) Restrictions. An analyst may not modify an approved analytical
method for a method-defined analyte. In addition, an analyst may not
modify an approved method if the modification would result in
measurement of a different form or species of an analyte (e.g., a change
to a metals digestion or total cyanide distillation). An analyst may
also may not modify any sample preservation and/or holding time
requirements of an approved method.
(c) Analytical requirements for multi-analyte methods (Target
Analytes). For the purpose of NPDES reporting, the discharger or
permittee must meet QC requirements only for the analyte(s) being
measured and reported under the NPDES permit.
(d) The following modifications to approved methods are authorized
in the circumstances described below:
(1) Capillary column. Use of a capillary (open tubular) GC column
rather than a packed column is allowed with EPA Methods 601-613, 624,
625, and 1624B in Appendix A to this part, provided that all QC tests
for the approved method are performed and all QC acceptance criteria are
met. When changing from a packed column to a capillary column, retention
times will change. Analysts are not required to meet retention time
specified in the approved method when this change is made. Instead,
analysts must generate new retention time tables with capillary columns
to be kept on file along with other startup test and ongoing QC data,
for review by auditors.
(2) Increased sample volume in purge and trap methodology. Use of
increased sample volumes, up to a maximum of 25 mL, is allowed for an
approved method, provided that the height of the water column in the
purge vessel is at least 5 cm. The analyst should also use one or more
surrogate analytes that are chemically similar to the analytes of
interest in order to demonstrate that the increased sample volume does
not adversely affect the analytical results.
[72 FR 11239, Mar. 12, 2007]
[[Page 64]]
Sec. Appendix A to Part 136--Methods for Organic Chemical Analysis of
Municipal and Industrial Wastewater
Method 601--Purgeable Halocarbons
1. Scope and Application
1.1 This method covers the determination of 29 purgeable
halocarbons.
The following parameters may be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
Bromodichloromethane........................... 32101 75-27-4
Bromoform...................................... 32104 75-25-2
Bromomethane................................... 34413 74-83-9
Carbon tetrachloride........................... 32102 56-23-5
Chlorobenzene.................................. 34301 108-90-7
Chloroethane................................... 34311 75-00-3
2-Chloroethylvinyl ether....................... 34576 100-75-8
Chloroform..................................... 32106 67-66-3
Chloromethane.................................. 34418 74-87-3
Dibromochloromethane........................... 32105 124-48-1
1,2-Dichlorobenzene............................ 34536 95-50-1
1,3-Dichlorobenzene............................ 34566 541-73-1
1,4-Dichlorobenzene............................ 34571 106-46-7
Dichlorodifluoromethane........................ 34668 75-71-8
1,1-Dichloroethane............................. 34496 75-34-3
1,2-Dichloroethane............................. 34531 107-06-2
1,1-Dichloroethane............................. 34501 75-35-4
trans-1,2-Dichloroethene....................... 34546 156-60-5
1,2-Dichloropropane............................ 34541 78-87-5
cis-1,3-Dichloropropene........................ 34704 10061-01-5
trans-1,3-Dichloropropene...................... 34699 10061-02-6
Methylene chloride............................. 34423 75-09-2
1,1,2,2-Tetrachloroethane...................... 34516 79-34-5
Tetrachloroethene.............................. 34475 127-18-4
1,1,1-Trichloroethane.......................... 34506 71-55-6
1,1,2-Trichloroethane.......................... 34511 79-00-5
Tetrachloroethene.............................. 39180 79-01-6
Trichlorofluoromethane......................... 34488 75-69-4
Vinyl chloride................................. 39715 75-01-4
------------------------------------------------------------------------
1.2 This is a purge and trap gas chromatographic (GC) method
applicable to the determination of the compounds listed above in
municipal and industrial discharges as provided under 40 CFR 136.1. When
this method is used to analyze unfamiliar samples for any or all of the
compounds above, compound identifications should be supported by at
least one additional qualitative technique. This method describes
analytical conditions for a second gas chromatographic column that can
be used to confirm measurements made with the primary column. Method 624
provides gas chromatograph/mass spectrometer (GC/MS) conditions
appropriate for the qualitative and quantitative confirmation of results
for most of the parameters listed above.
1.3 The method detection limit (MDL, defined in Section 12.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the operation of a purge and trap system and a
gas chromatograph and in the interpretation of gas chromatograms. Each
analyst must demonstrate the ability to generate acceptable results with
this method using the procedure described in Section 8.2.
2. Summary of Method
2.1 An inert gas is bubbled through a 5-mL water sample contained in
a specially-designed purging chamber at ambient temperature. The
halocarbons are efficiently transferred from the aqueous phase to the
vapor phase. The vapor is swept through a sorbent trap where the
halocarbons are trapped. After purging is completed, the trap is heated
and backflushed with the inert gas to desorb the halocarbons onto a gas
chromatographic column. The gas chromatograph is temperature programmed
to separate the halocarbons which are then detected with a halide-
specific detector. \2,3\
2.2 The method provides an optional gas chromatographic column that
may be helpful in resolving the compounds of interest from interferences
that may occur.
3. Interferences
3.1 Impurities in the purge gas and organic compounds outgassing
from the plumbing ahead of the trap account for the majority of
contamination problems. The analytical system must be demonstrated to be
free from contamination under the conditions of the analysis by running
laboratory reagent blanks as described in Section 8.1.3. The use of non-
Teflon plastic tubing, non-Teflon thread sealants, or flow controllers
with rubber components in the purge and trap system should be avoided.
3.2 Samples can be contaminated by diffusion of volatile organics
(particularly fluorocarbons and methylene chloride) through the septum
seal ilto the sample during shipment and storage. A field reagent blank
prepared from reagent water and carried through the sampling and
handling protocol can serve as a check on such contamination.
3.3 Contamination by carry-over can occur whenever high level and
low level samples are sequentially analyzed. To reduce carry-over, the
purging device and sample syringe must be rinsed with reagent water
between sample analyses. Whenever an unusually concentrated sample is
encountered, it should be followed by an analysis of reagent water to
check for cross contamination. For samples containing large amounts of
water-soluble materials, suspended solids,
[[Page 65]]
high boiling compounds or high organohalide levels, it may be necessary
to wash out the purging device with a detergent solution, rinse it with
distilled water, and then dry it in a 105[deg]C oven between analyses.
The trap and other parts of the system are also subject to
contamination; therefore, frequent bakeout and purging of the entire
system may be required.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \4,6\ for
the information of the analyst.
4.2 The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: carbon tetrachloride, chloroform, 1,4-dichlorobenzene, and
vinyl chloride. Primary standards of these toxic compounds should be
prepared in a hood. A NIOSH/MESA approved toxic gas respirator should be
worn when the analyst handles high concentrations of these toxic
compounds.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete sampling.
5.1.1 Vial--25-mL capacity or larger, equipped with a screw cap with
a hole in the center (Pierce 13075 or equivalent). Detergent
wash, rinse with tap and distilled water, and dry at 105 [deg]C before
use.
5.1.2 Septum--Teflon-faced silicone (Pierce 12722 or
equivalent). Detergent wash, rinse with tap and distilled water, and dry
at 105 [deg]C for 1 h before use.
5.2 Purge and trap system--The purge and trap system consists of
three separate pieces of equipment: a purging device, trap, and
desorber. Several complete systems are now commercially available.
5.2.1 The purging device must be designed to accept 5-mL samples
with a water column at least 3 cm deep. The gaseous head space between
the water column and the trap must have a total volume of less than 15
mL. The purge gas must pass through the water column as finely divided
bubbles with a diameter of less than 3 mm at the origin. The purge gas
must be introduced no more than 5 mm from the base of the water column.
The purging device illustrated in Figure 1 meets these design criteria.
5.2.2 The trap must be at least 25 cm long and have an inside
diameter of at least 0.105 in. The trap must be packed to contain the
following minimum lengths of adsorbents: 1.0 cm of methyl silicone
coated packing (Section 6.3.3), 7.7 cm of 2,6-diphenylene oxide polymer
(Section 6.3.2), 7.7 cm of silica gel (Section 6.3.4), 7.7 cm of coconut
charcoal (Section 6.3.1). If it is not necessary to analyze for
dichlorodifluoromethane, the charcoal can be eliminated, and the polymer
section lengthened to 15 cm. The minimum specifications for the trap are
illustrated in Figure 2.
5.2.3 The desorber must be capable of rapidly heating the trap to
180 [deg]C. The polymer section of the trap should not be heated higher
than 180 [deg]C and the remaining sections should not exceed 200 [deg]C.
The desorber illustrated in Figure 2 meets these design criteria.
5.2.4 The purge and trap system may be assembled as a separate unit
or be coupled to a gas chromatograph as illustrated in Figures 3 and 4.
5.3 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, gases, detector, and strip-chart recorder. A data system is
recommended for measuring peak areas.
5.3.1 Column 1--8 ft long x 0.1 in. ID stainless steel or glass,
packed with 1% SP-1000 on Carbopack B (60/80 mesh) or equivalent. This
column was used to develop the method performance statements in Section
12. Guidelines for the use of alternate column packings are provided in
Section 10.1.
5.3.2 Column 2--6 ft long x 0.1 in. ID stainless steel or glass,
packed with chemically bonded n-octane on Porasil-C (100/120 mesh) or
equivalent.
5.3.3 Detector--Electrolytic conductivity or microcoulometric
detector. These types of detectors have proven effective in the analysis
of wastewaters for the parameters listed in the scope (Section 1.1). The
electrolytic conductivity detector was used to develop the method
performance statements in Section 12. Guidelines for the use of
alternate detectors are provided in Section 10.1.
5.4 Syringes--5-mL glass hypodermic with Luerlok tip (two each), if
applicable to the purging device.
5.5 Micro syringes--25-[micro]L, 0.006 in. ID needle.
5.6 Syringe valve--2-way, with Luer ends (three each).
5.7 Syringe--5-mL, gas-tight with shut-off valve.
5.8 Bottle--15-mL, screw-cap, with Teflon cap liner.
[[Page 66]]
5.9 Balance--Analytical, capable of accurately weighing 0.0001 g.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.1.1 Reagent water can be generated by passing tap water through a
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
6.1.2 A water purification system (Millipore Super-Q or equivalent)
may be used to generate reagent water.
6.1.3 Reagent water may also be prepared by boiling water for 15
min. Subsequently, while maintaining the temperature at 90 [deg]C,
bubble a contaminant-free inert gas through the water for 1 h. While
still hot, transfer the water to a narrow mouth screw-cap bottle and
seal with a Teflon-lined septum and cap.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Trap Materials:
6.3.1 Coconut charcoal--6/10 mesh sieved to 26 mesh, Barnabey
Cheney, CA-580-26 lot M-2649 or equivalent.
6.3.2 2,6-Diphenylene oxide polymer--Tenax, (60/80 mesh),
chromatographic grade or equivalent.
6.3.3 Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh)
or equivalent.
6.3.4 Silica gel--35/60 mesh, Davison, grade-15 or equivalent.
6.4 Methanol--Pesticide quality or equivalent.
6.5 Stock standard solutions--Stock standard solutions may be
prepared from pure standard materials or purchased as certified
solutions. Prepare stock standard solutions in methanol using assayed
liquids or gases as appropriate. Because of the toxicity of some of the
organohalides, primary dilutions of these materials should be prepared
in a hood. A NIOSH/MESA approved toxic gas respirator should be used
when the analyst handles high concentrations of such materials.
6.5.1 Place about 9.8 mL of methanol into a 10-mL ground glass
stoppered volumetric flask. Allow the flask to stand, unstoppered, for
about 10 min or until all alcohol wetted surfaces have dried. Weigh the
flask to the learest 0.1 mg.
6.5.2 Add the assayed reference material:
6.5.2.1 Liquid--Using a 100 [micro]L syringe, immediately add two or
more drops of assayed reference material to the flask, then reweigh. Be
sure that the drops fall directly into the alcohol without contacting
the neck of the flask.
6.5.2.2 Gases--To prepare standards for any of the six halocarbons
that boil below 30 [deg] C (bromomethane, chloroethane, chloromethane,
dichlorodifluoromethane, trichlorofluoromethane, vinyl chloride), fill a
5-mL valved gas-tight syringe with the reference standard to the 5.0-mL
mark. Lower the needle to 5 mm above the methanol meniscus. Slowly
introduce the reference standard above the surface of the liquid (the
heavy gas will rapidly dissolve into the methanol).
6.5.3 Reweigh, dilute to volume, stopper, then mix by inverting the
flask several times. Calculate the concentration in [micro]g/[micro]L
from the net gain in weight. When compound purity is assayed to be 96%
or greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
malufacturer or by an independent source.
6.5.4 Transfer the stock standard solution into a Teflon-sealed
screw-cap bottle. Store, with minimal headspace, at -10 to -20 [deg]C
and protect from light.
6.5.5 Prepare fresh standards weekly for the six gases and 2-
chloroethylvinyl ether. All other standards must be replaced after one
month, or sooner if comparison with check standards indicates a problem.
6.6 Secondary dilution standards--Using stock standard solutions,
prepare secondary dilution standards in methanol that contain the
compounds of interest, either singly or mixed together. The secondary
dilution standards should be prepared at concentrations such that the
aqueous calibration standards prepared in Section 7.3.1 or 7.4.1 will
bracket the working range of the analytical system. Secondary dilution
standards should be stored with minimal headspace and should be checked
frequently for signs of degradation or evaporation, especially just
prior to preparing calibration standards from them.
6.7 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Assemble a purge and trap system that meets the specifications
in Section 5.2. Condition the trap overnight at 180 [deg]C by
backflushing with an inert gas flow of at least 20 mL/min. Condition the
trap for 10 min once daily prior to use.
7.2 Connect the purge and trap system to a gas chromatograph. The
gas chromatograph must be operated using temperature and flow rate
conditions equivalent to those given in Table 1. Calibrate the purge and
trap-gas chromatographic system using either the external standard
technique (Section 7.3) or the internal standard technique (Section
7.4).
7.3 External standard calibration procedure:
7.3.1 Prepare calibration standards at a miminum of three
concentration levels for each parameter by carefully adding 20.0
[micro]L of one or more secondary dilution standards to 100, 500, or
1000 [micro]L of reagent water. A 25-[micro]L
[[Page 67]]
syringe with a 0.006 in. ID needle should be used for this operation.
One of the external standards should be at a concentration near, but
above, the MDL (Table 1) and the other concentrations should correspond
to the expected range of concentrations found in real samples or should
define the working range of the detector. These aqueous standards can be
stored up to 24 h, if held in sealed vials with zero headspace as
described in Section 9.2. If not so stored, they must be discarded after
1 h.
7.3.2 Analyze each calibration standard according to Section 10, and
tabulate peak height or area responses versus the concentration in the
standard. The results can be used to prepare a calibration curve for
each compound. Alternatively, if the ratio of response to concentration
(calibration factor) is a constant over the working range (<10% relative
standard deviation, RSD), linearity through the origin can be assumed
and the average ratio or calibration factor can be used in place of a
calibration curve.
7.4 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples. The compounds recommended for use as surrogate spikes in
Section 8.7 have been used successfully as internal standards, because
of their generally unique retention times.
7.4.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest as described in
Section 7.3.1.
7.4.2 Prepare a spiking solution containing each of the internal
standards using the procedures described in Sections 6.5 and 6.6. It is
recommended that the secondary dilution standard be prepared at a
concentration of 15 [micro]g/mL of each internal standard compound. The
addition of 10 [micro]L of this standard to 5.0 mL of sample or
calibration standard would be equivalent to 30 [micro]g/L.
7.4.3 Analyze each calibration standard according to Section 10,
adding 10 [micro]L of internal standard spiking solution directly to the
syringe (Section 10.4). Tabulate peak height or area responses against
concentration for each compound and internal standard, and calculate
response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.094
Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard.
Cs=Concentration of the parameter to be measured.
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.5 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of a QC check sample.
7.5.1 Prepare the QC check sample as described in Section 8.2.2.
7.5.2 Analyze the QC check sample according to Section 10.
7.5.3 For each parameter, compare the response (Q) with the
corresponding calibration acceptance criteria found in Table 2. If the
responses for all parameters of interest fall within the designated
ranges, analysis of actual samples can begin. If any individual Q falls
outside the range, proceed according to Section 7.5.4.
Note: The large number of parameters in Table 2 present a
substantial probability that one or more will not meet the calibration
acceptance criteria when all parameters are analyzed.
7.5.4 Repeat the test only for those parameters that failed to meet
the calibration acceptance criteria. If the response for a parameter
does not fall within the range in this second test, a new calibration
curve, calibration factor, or RF must be prepared for that parameter
according to Section 7.3 or 7.4.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision
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with this method. This ability is established as described in Section
8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Section 10.1) to improve the separations or lower the cost of
measurements. Each time such a modification is made to the method, the
analyst is required to repeat the procedure in Section 8.2.
8.1.3 Each day, the analyst must analyze a reagent water blank to
demonstrate that interferences from the analytical system are under
control.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 10 [micro]g/
mL in methanol. The QC check sample concentrate must be obtained from
the U.S. Environmental Protection Agency, Environmental Monitoring and
Support Laboratory in Cincinnati, Ohio, if available. If not available
from that source, the QC check sample concentrate must be obtained from
another external source. If not available from either source above, the
QC check sample concentrate must be prepared by the laboratory using
stock standards prepared independently from those used for calibration.
8.2.2 Prepare a QC check sample to contain 20 [micro]g/L of each
parameter by adding 200 [micro]L of QC check sample concentrate to 100
mL of reagent water.
8.2.3 Analyze four 5-mL aliquots of the well-mixed QC check sample
according to Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
of interest using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, then the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Table 2 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.3.
8.2.6.2 Beginning with Section 8.2.3, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compounds of interest beginning with Section 8.2.3.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 20 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.2 Analyze one 5-mL sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second 5-mL sample aliquot with 10
[micro]L of the QC check sample concentrate and analyze it to determine
the concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement
[[Page 69]]
of both the background and spike concentrations, assuming a spike to
background ratio of 5:1. This error will be accounted for to the extent
that the analyst's spike to background ratio approaches 5:1. \7\ If
spiking was performed at a concentration lower than 20 [micro]g/L, the
analyst must use either the QC acceptance criteria in Table 2, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 3, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 3,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T)2.44(100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory. If the entire list of parameters in Table 2 must be measured
in the sample in Section 8.3, the probability that the analysis of a QC
check standard will be required is high. In this case the QC check
standard should be routinely analyzed with the spiked sample.
8.4.1 Prepare the QC check standard by adding 10 [micro]L of QC
check sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent
water. The QC check standard needs only to contain the parameters that
failed criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If p=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
8.7 The analyst should monitor both the performance of the
analytical system and the effectiveness of the method in dealing with
each sample matrix by spiking each sample, standard, and reagent water
blank with surrogate halocarbons. A combination of bromochloromethane,
2-bromo-1-chloropropane, and 1,4-dichlorobutane is recommended to
encompass the range of the temperature program used in this method. From
stock standard solutions prepared as in Section 6.5, add a volume to
give 750 [micro]g of each surrogate to 45 mL of reagent water contained
in a 50-mL volumetric flask, mix and dilute to volume for a
concentration of 15 ng/[micro]L. Add 10 [micro]L of this surrogate
spiking solution directly into the 5-mL syringe with every sample and
reference standard analyzed. Prepare a fresh surrogate spiking solution
on a weekly basis. If the internal standard calibration procedure is
being used, the surrogate compounds may be added directly to the
internal standard spiking solution (Section 7.4.2).
9. Sample Collection, Preservation, and Handling
9.1 All samples must be iced or refrigerated from the time of
collection until analysis. If the sample contains free or combined
chlorine, add sodium thiosulfate preservative (10 mg/40 mL is sufficient
for up to 5 ppm Cl2) to the empty sample bottle just prior to
shipping to the sampling site. EPA Methods 330.4 and 330.5 may be used
for measurement of residual chlorine. \8\ Field test kits are available
for this purpose.
9.2 Grab samples must be collected in glass containers having a
total volume of at least 25 mL. Fill the sample bottle just to
overflowing in such a manner that no air
[[Page 70]]
bubbles pass through the sample as the bottle is being filled. Seal the
bottle so that no air bubbles are entrapped in it. If preservative has
been added, shake vigorously for 1 min. Maintain the hermetic seal on
the sample bottle until time of analysis.
9.3 All samples must be analyzed within 14 days of collection. \3\
10. Procedure
10.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are estimated retention times
and MDL that can be achieved under these conditions. An example of the
separations achieved by Column 1 is shown in Figure 5. Other packed
columns, chromatographic conditions, or detectors may be used if the
requirements of Section 8.2 are met.
10.2 Calibrate the system daily as described in Section 7.
10.3 Adjust the purge gas (nitrogen or helium) flow rate to 40 mL/
min. Attach the trap inlet to the purging device, and set the purge and
trap system to purge (Figure 3). Open the syringe valve located on the
purging device sample introduction needle.
10.4 Allow the sample to come to ambient temperature prior to
introducing it to the syringe. Remove the plunger from a 5-mL syringe
and attach a closed syringe valve. Open the sample bottle (or standard)
and carefully pour the sample into the syringe barrel to just short of
overflowing. Replace the syringe plunger and compress the sample. Open
the syringe valve and vent any residual air while adjusting the sample
volume to 5.0 mL. Since this process of taking an aliquot destroys the
validity of the sample for future analysis, the analyst should fill a
second syringe at this time to protect against possible loss of data.
Add 10.0 [micro]L of the surrogate spiking solution (Section 8.7) and
10.0 [micro]L of the internal standard spiking solution (Section 7.4.2),
if applicable, through the valve bore, then close the valve.
10.5 Attach the syringe-syringe valve assembly to the syringe valve
on the purging device. Open the syringe valves and inject the sample
into the purging chamber.
10.6 Close both valves and purge the sample for 11.0 0.1 min at ambient temperature.
10.7 After the 11-min purge time, attach the trap to the
chromatograph, adjust the purge and trap system to the desorb mode
(Figure 4), and begin to temperature program the gas chromatograph.
Introduce the trapped materials to the GC column by rapidly heating the
trap to 180 [deg]C while backflushing the trap with an inert gas between
20 and 60 mL/min for 4 min. If rapid heating of the trap cannot be
achieved, the GC column must be used as a secondary trap by cooling it
to 30 [deg]C (subambient temperature, if poor peak geometry or random
retention time problems persist) instead of the initial program
temperature of 45 [deg]C
10.8 While the trap is being desorbed into the gas chromatograph,
empty the purging chamber using the sample introduction syringe. Wash
the chamber with two 5-mL flushes of reagent water.
10.9 After desorbing the sample for 4 min, recondition the trap by
returning the purge and trap system to the purge mode. Wait 15 s then
close the syringe valve on the purging device to begin gas flow through
the trap. The trap temperature should be maintained at 180 [deg]C After
approximately 7 min, turn off the trap heater and open the syringe valve
to stop the gas flow through the trap. When the trap is cool, the next
sample can be analyzed.
10.10 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
10.11 If the response for a peak exceeds the working range of the
system, prepare a dilution of the sample with reagent water from the
aliquot in the second syringe and reanalyze.
11. Calculations
11.1 Determine the concentration of individual compounds in the
sample.
11.1.1 If the external standard calibration procedure is used,
calculate the concentration of the parameter being measured from the
peak response using the calibration curve or calibration factor
determined in Section 7.3.2.
11.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.4.3 and Equation 2.
Equation 2
[GRAPHIC] [TIFF OMITTED] TC15NO91.095
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard.
11.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
[[Page 71]]
12. Method Performance
12.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentration
listed in Table 1 were obtained using reagent water. \11\. Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
12.2 This method is recommended for use in the concentration range
from the MDL to 1000xMDL. Direct aqueous injection techniques should be
used to measure concentration levels above 1000xMDL.
12.3 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 8.0 to 500 [micro]g/L. \9\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. Bellar, T.A., and Lichtenberg, J.J. ``Determining Volatile
Organics at Microgram-per-Litre-Levels by Gas Chromatography,'' Journal
of the American Water Works Association, 66, 739 (1974).
3. Bellar, T.A., and Lichtenberg, J.J. ``Semi-Automated Headspace
Analysis of Drinking Waters and Industrial Waters for Purgeable Volatile
Organic Compounds,'' Proceedings from Symposium on Measurement of
Organic Pollutants in Water and Wastewater, American Society for Testing
and Materials, STP 686, C.E. Van Hall, editor, 1978.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
8. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA 600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
9. ``EPA Method Study 24, Method 601--Purgeable Halocarbons by the
Purge and Trap Method,'' EPA 600/4-84-064, National Technical
Information Service, PB84-212448, Springfield, Virginia 22161, July
1984.
10. ``Method Validation Data for EPA Method 601,'' Memorandum from
B. Potter, U.S. Environmental Protection Agency, Environmental
Monitoring and Support Laboratory, Cincinnati, Ohio 45268, November 10,
1983.
11. Bellar, T. A., Unpublished data, U.S. Environmental Protection
Agency, Environmental Monitoring and Support Laboratory, Cincinnati,
Ohio 45268, 1981.
Table 1--Chromatographic Conditions and Method Detection Limits
----------------------------------------------------------------------------------------------------------------
Retention time (min) Method detection
Parameter ------------------------------------ limit ([micro]g/
Column 1 Column 2 L)
----------------------------------------------------------------------------------------------------------------
Chloromethane............................................. 1.50 5.28 0.08
Bromomethane.............................................. 2.17 7.05 1.18
Dichlorodifluoromethane................................... 2.62 nd 1.81
Vinyl chloride............................................ 2.67 5.28 0.18
Chloroethane.............................................. 3.33 8.68 0.52
Methylene chloride........................................ 5.25 10.1 0.25
Trichlorofluoromethane.................................... 7.18 nd nd
1,1-Dichloroethene........................................ 7.93 7.72 0.13
1,1-Dichloroethane........................................ 9.30 12.6 0.07
trans-1,2-Dichloroethene.................................. 10.1 9.38 0.10
Chloroform................................................ 10.7 12.1 0.05
1,2-Dichloroethane........................................ 11.4 15.4 0.03
1,1,1-Trichloroethane..................................... 12.6 13.1 0.03
Carbon tetrachloride...................................... 13.0 14.4 0.12
Bromodichloromethane...................................... 13.7 14.6 0.10
1,2-Dichloropropane....................................... 14.9 16.6 0.04
cis-1,3-Dichloropropene................................... 15.2 16.6 0.34
Trichloroethene........................................... 15.8 13.1 0.12
Dibromochloromethane...................................... 16.5 16.6 0.09
[[Page 72]]
1,1,2-Trichloroethane..................................... 16.5 18.1 0.02
trans-1,3-Dichloropropene................................. 16.5 18.0 0.20
2-Chloroethylvinyl ether.................................. 18.0 nd 0.13
Bromoform................................................. 19.2 19.2 0.20
1,1,2,2-Tetrachloroethane................................. 21.6 nd 0.03
Tetrachloroethene......................................... 21.7 15.0 0.03
Chlorobenzene............................................. 24.2 18.8 0.25
1,3-Dichlorobenzene....................................... 34.0 22.4 0.32
1,2-Dichlorobenzene....................................... 34.9 23.5 0.15
1,4-Dichlorobenzene....................................... 35.4 22.3 0.24
----------------------------------------------------------------------------------------------------------------
Column 1 conditions: Carbopack B (60/80 mesh) coated with 1% SP-1000 packed in an 8 ft x 0.1 in. ID stainless
steel or glass column with helium carrier gas at 40 mL/min flow rate. Column temperature held at 45 [deg]C for
3 min then programmed at 8 [deg]C/min to 220 [deg]C and held for 15 min.
Column 2 conditions: Porisil-C (100/120 mesh) coated with n-octane packed in a 6 ft x 0.1 in. ID stainless steel
or glass column with helium carrier gas at 40 mL/min flow rate. Column temperature held at 50 [deg]C for 3 min
then programmed at 6 [deg]C/min to 170 [deg]C and held for 4 min.
nd=not determined.
Table 2--Calibration and QC Acceptance Criteria--Method 601 \a\
----------------------------------------------------------------------------------------------------------------
Limit for
Range for Q s Range for X Range P,
Parameter ([micro]g/L) ([micro]g/ ([micro]g/L) Ps (%)
L)
----------------------------------------------------------------------------------------------------------------
Bromodichloromethane.................................... 15.2-24.8 4.3 10.7-32.0 42-172
Bromoform............................................... 14.7-25.3 4.7 5.0-29.3 13-159
Bromomethane............................................ 11.7-28.3 7.6 3.4-24.5 D-144
Carbon tetrachloride.................................... 13.7-26.3 5.6 11.8-25.3 43-143
Chlorobenzene........................................... 14.4-25.6 5.0 10.2-27.4 38-150
Chloroethane............................................ 15.4-24.6 4.4 11.3-25.2 46-137
2-Chloroethylvinyl ether................................ 12.0-28.0 8.3 4.5-35.5 14-186
Chloroform.............................................. 15.0-25.0 4.5 12.4-24.0 49-133
Chloromethane........................................... 11.9-28.1 7.4 D-34.9 D-193
Dibromochloromethane.................................... 13.1-26.9 6.3 7.9-35.1 24-191
1,2-Dichlorobenzene..................................... 14.0-26.0 5.5 1.7-38.9 D-208
1,3-Dichlorobenzene..................................... 9.9-30.1 9.1 6.2-32.6 7-187
1,4-Dichlorobenzene..................................... 13.9-26.1 5.5 11.5-25.5 42-143
1,1-Dichloroethane...................................... 16.8-23.2 3.2 11.2-24.6 47-132
1,2-Dichloroethane...................................... 14.3-25.7 5.2 13.0-26.5 51-147
1,1-Dichloroethene...................................... 12.6-27.4 6.6 10.2-27.3 28-167
trans-1,2-Dichloroethene................................ 12.8-27.2 6.4 11.4-27.1 38-155
1,2-Dichloropropane..................................... 14.8-25.2 5.2 10.1-29.9 44-156
cis-1,3-Dichloropropene................................. 12.8-27.2 7.3 6.2-33.8 22-178
trans-1,3-Dichloropropene............................... 12.8-27.2 7.3 6.2-33.8 22-178
Methylene chloride...................................... 15.5-24.5 4.0 7.0-27.6 25-162
1,1,2,2-Tetrachloroethane............................... 9.8-30.2 9.2 6.6-31.8 8-184
Tetrachloroethene....................................... 14.0-26.0 5.4 8.1-29.6 26-162
1,1,1-Trichloroethane................................... 14.2-25.8 4.9 10.8-24.8 41-138
1,1,2-Trichloroethane................................... 15.7-24.3 3.9 9.6-25.4 39-136
Trichloroethene......................................... 15.4-24.6 4.2 9.2-26.6 35-146
Trichlorofluoromethane.................................. 13.3-26.7 6.0 7.4-28.1 21-156
Vinyl chloride.......................................... 13.7-26.3 5.7 8.2-29.9 28-163
----------------------------------------------------------------------------------------------------------------
\a\ Criteria were calculated assuming a QC check sample concentration of 20 [micro]g/L.
Q=Concentration measured in QC check sample, in [micro]g/L (Section 7.5.3).
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 601
----------------------------------------------------------------------------------------------------------------
Single analyst
Parameter Accuracy, as recovery, precision, sr' Overall precision, S'
X' ([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Bromodichloromethane................ 1.12C-1.02 0.11X+0.04 0.20X+1.00
Bromoform........................... 0.96C-2.05 0.12X+0.58 0.21X+2.41
Bromomethane........................ 0.76C-1.27 0.28X+0.27 0.36X+0.94
Carbon tetrachloride................ 0.98C-1.04 0.15X+0.38 0.20X+0.39
Chlorobenzene....................... 1.00C-1.23 0.15X-0.02 0.18X+1.21
Choroethane......................... 0.99C-1.53 0.14X-0.13 0.17X+0.63
[[Page 73]]
2-Chloroethylvinyl ether \a\........ 1.00C 0.20X 0.35X
Chloroform.......................... 0.93C-0.39 0.13X+0.15 0.19X-0.02
Chloromethane....................... 0.77C+0.18 0.28X-0.31 0.52X+1.31
Dibromochloromethane................ 0.94C+2.72 0.11X+1.10 0.24X+1.68
1,2-Dichlorobenzene................. 0.93C+1.70 0.20X+0.97 0.13X+6.13
1,3-Dichlorobenzene................. 0.95C+0.43 0.14X+2.33 0.26X+2.34
1,4-Dichlorobenzene................. 0.93C-0.09 0.15X+0.29 0.20X+0.41
1,1-Dichloroethane.................. 0.95C-1.08 0.09X+0.17 0.14X+0.94
1,2-Dichloroethane.................. 1.04C-1.06 0.11X+0.70 0.15X+0.94
1,1-Dichloroethene.................. 0.98C-0.87 0.21X-0.23 0.29X-0.40
trans-1,2-Dichloroethene............ 0.97C-0.16 0.11X+1.46 0.17X+1.46
1,2-Dichloropropane \a\............. 1.00C 0.13X 0.23X
cis-1,3-Dichloropropene \a\......... 1.00C 0.18X 0.32X
trans-1,3-Dichloropropene \a\....... 1.00C 0.18X 0.32X
Methylene chloride.................. 0.91C-0.93 0.11X+0.33 0.21X+1.43
1,1,2,2-Tetrachloroethene........... 0.95C+0.19 0.14X+2.41 0.23X+2.79
Tetrachloroethene................... 0.94C+0.06 0.14X+0.38 0.18X+2.21
1,1,1-Trichloroethane............... 0.90C-0.16 0.15X+0.04 0.20X+0.37
1,1,2-Trichloroethane............... 0.86C+0.30 0.13X-0.14 0.19X+0.67
Trichloroethene..................... 0.87C+0.48 0.13X-0.03 0.23X+0.30
Trichlorofluoromethane.............. 0.89C-0.07 0.15X+0.67 0.26X+0.91
Vinyl chloride...................... 0.97C-0.36 0.13X+0.65 0.27X+0.40
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sn'=Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S\1\=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
\a\ Estimates based upon the performance in a single laboratory. \10\
[[Page 74]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.000
[[Page 75]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.001
[[Page 76]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.002
[[Page 77]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.003
[[Page 78]]
Method 602--Purgeable Aromatics
1. Scope and Application
1.1 This method covers the determination of various purgeable
aromatics. The following parameters may be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
Benzene.......................................... 34030 71-43-2
Chlorobenzene.................................... 34301 108-90-7
1,2-Dichlorobenzene.............................. 34536 95-50-1
1,3-Dichlorobenzene.............................. 34566 541-73-1
1,4-Dichlorobenzene.............................. 34571 106-46-7
Ethylbenzene..................................... 34371 100-41-4
Toluene.......................................... 34010 108-88-3
------------------------------------------------------------------------
1.2 This is a purge and trap gas chromatographic (GC) method
applicable to the determination of the compounds listed above in
municipal and industrial discharges as provided under 40 CFR 136.1. When
this method is used to analyze unfamiliar samples for any or all of the
compounds above, compound identifications should be supported by at
least one additional qualitative technique. This method describes
analytical conditions for a second gas chromatographic column that can
be used to confirm measurements made with the primary column. Method 624
provides gas chromatograph/mass spectrometer (GC/MS) conditions
appropriate for the qualitative and quantitative confirmation of results
for all of the parameters listed above.
1.3 The method detection limit (MDL, defined in Section 12.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the operation of a purge and trap system and a
gas chromatograph and in the interpretation of gas chromatograms. Each
analyst must demonstrate the ability to generate acceptable results with
this method using the procedure described in Section 8.2.
2. Summary of Method
2.1 An inert gas is bubbled through a 5-mL water sample contained in
a specially-designed purging chamber at ambient temperature. The
aromatics are efficiently transferred from the aqueous phase to the
vapor phase. The vapor is swept through a sorbent trap where the
aromatics are trapped. After purging is completed, the trap is heated
and backflushed with the inert gas to desorb the aromatics onto a gas
chromatographic column. The gas chromatograph is temperature programmed
to separate the aromatics which are then detected with a photoionization
detector. \2,3\
2.2 The method provides an optional gas chromatographic column that
may be helpful in resolving the compounds of interest from interferences
that may occur.
3. Interferences
3.1 Impurities in the purge gas and organic compounds outgassing
from the plumbing ahead of the trap account for the majority of
contamination problems. The analytical system must be demonstrated to be
free from contamination under the conditions of the analysis by running
laboratory reagent blanks as described in Section 8.1.3. The use of non-
Teflon plastic tubing, non-Teflon thread sealants, or flow controllers
with rubber components in the purge and trap system should be avoided.
3.2 Samples can be contaminated by diffusion of volatile organics
through the septum seal into the sample during shipment and storage. A
field reagent blank prepared from reagent water and carried through the
sampling and handling protocol can serve as a check on such
contamination.
3.3 Contamination by carry-over can occur whenever high level and
low level samples are sequentially analyzed. To reduce carry-over, the
purging device and sample syringe must be rinsed with reagent water
between sample analyses. Whenever an unusually concentrated sample is
encountered, it should be followed by an analysis of reagent water to
check for cross contamination. For samples containing large amounts of
water-soluble materials, suspended solids, high boiling compounds or
high aromatic levels, it may be necessary to wash the purging device
with a detergent solution, rinse it with distilled water, and then dry
it in an oven at 105 [deg]C between analyses. The trap and other parts
of the system are also subject to contamination; therefore, frequent
bakeout and purging of the entire system may be required.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety
[[Page 79]]
are available and have been identified \4,6\ for the information of the
analyst.
4.2 The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: benzene and 1,4-dichlorobenzene. Primary standards of these
toxic compounds should be prepared in a hood. A NIOSH/MESA approved
toxic gas respirator should be worn when the analyst handles high
concentrations of these toxic compounds.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete sampling.
5.1.1 Vial]25-mL capacity or larger, equipped with a screw cap with
a hole in the center (Pierce 13075 or equivalent). Detergent
wash, rinse with tap and distilled water, and dry at 105 [deg]C before
use.
5.1.2 Septum--Teflon-faced silicone (Pierce 12722 or
equivalent). Detergent wash, rinse with tap and distilled water, and dry
at 105 [deg]C for 1 h before use.
5.2 Purge and trap system--The purge and trap system consists of
three separate pieces of equipment: A purging device, trap, and
desorber. Several complete systems are now commercially available.
5.2.1 The purging device must be designed to accept 5-mL samples
with a water column at least 3 cm deep. The gaseous head space between
the water column and the trap must have a total volume of less than 15
mL. The purge gas must pass through the water column as finely divided
bubbles with a diameter of less than 3 mm at the origin. The purge gas
must be introduced no more than 5 mm from the base of the water column.
The purging device illustrated in Figure 1 meets these design criteria.
5.2.2 The trap must be at least 25 cm long and have an inside
diameter of at least 0.105 in.
5.2.2.1 The trap is packed with 1 cm of methyl silicone coated
packing (Section 6.4.2) and 23 cm of 2,6-diphenylene oxide polymer
(Section 6.4.1) as shown in Figure 2. This trap was used to develop the
method performance statements in Section 12.
5.2.2.2 Alternatively, either of the two traps described in Method
601 may be used, although water vapor will preclude the measurement of
low concentrations of benzene.
5.2.3 The desorber must be capable of rapidly heating the trap to
180 [deg]C. The polymer section of the trap should not be heated higher
than 180 [deg]C and the remaining sections should not exceed 200 [deg]C.
The desorber illustrated in Figure 2 meets these design criteria.
5.2.4 The purge and trap system may be assembled as a separate unit
or be coupled to a gas chromatograph as illustrated in Figures 3, 4, and
5.
5.3 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, gases, detector, and strip-chart recorder. A data system is
recommended for measuring peak areas.
5.3.1 Column 1--6 ft long x 0.082 in. ID stainless steel or glass,
packed with 5% SP-1200 and 1.75% Bentone-34 on Supelcoport (100/120
mesh) or equivalent. This column was used to develop the method
performance statements in Section 12. Guidelines for the use of
alternate column packings are provided in Section 10.1.
5.3.2 Column 2--8 ft long x 0.1 in ID stainless steel or glass,
packed with 5% 1,2,3-Tris(2-cyanoethoxy)propane on Chromosorb W-AW (60/
80 mesh) or equivalent.
5.3.3 Detector--Photoionization detector (h-Nu Systems, Inc. Model
PI-51-02 or equivalent). This type of detector has been proven effective
in the analysis of wastewaters for the parameters listed in the scope
(Section 1.1), and was used to develop the method performance statements
in Section 12. Guidelines for the use of alternate detectors are
provided in Section 10.1.
5.4 Syringes--5-mL glass hypodermic with Luerlok tip (two each), if
applicable to the purging device.
5.5 Micro syringes--25-[micro]L, 0.006 in. ID needle.
5.6 Syringe valve--2-way, with Luer ends (three each).
5.7 Bottle--15-mL, screw-cap, with Teflon cap liner.
5.8 Balance--Analytical, capable of accurately weighing 0.0001 g.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.1.1 Reagent water can be generated by passing tap water through a
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
6.1.2 A water purification system (Millipore Super-Q or equivalent)
may be used to generate reagent water.
6.1.3 Reagent water may also be prepared by boiling water for 15
min. Subsequently, while maintaining the temperature at 90 [deg]C,
bubble a contaminant-free inert gas through the water for 1 h. While
still hot, transfer the water to a narrow mouth screw-cap bottle and
seal with a Teflon-lined septum and cap.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Hydrochloric acid (1+1)--Add 50 mL of concentrated HCl (ACS) to
50 mL of reagent water.
6.4 Trap Materials:
[[Page 80]]
6.4.1 2,6-Diphenylene oxide polymer--Tenax, (60/80 mesh),
chromatographic grade or equivalent.
6.4.2 Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh)
or equivalent.
6.5 Methanol--Pesticide quality or equivalent.
6.6 Stock standard solutions--Stock standard solutions may be
prepared from pure standard materials or purchased as certified
solutions. Prepare stock standard solutions in methanol using assayed
liquids. Because of the toxicity of benzene and 1,4-dichlorobenzene,
primary dilutions of these materials should be prepared in a hood. A
NIOSH/MESA approved toxic gas respirator should be used when the analyst
handles high concentrations of such materials.
6.6.1 Place about 9.8 mL of methanol into a 10-mL ground glass
stoppered volumetric flask. Allow the flask to stand, unstoppered, for
about 10 min or until all alcohol wetted surfaces have dried. Weigh the
flask to the nearest 0.1 mg.
6.6.2 Using a 100-[micro]L syringe, immediately add two or more
drops of assayed reference material to the flask, then reweigh. Be sure
that the drops fall directly into the alcohol without contacting the
neck of the flask.
6.6.3 Reweigh, dilute to volume, stopper, then mix by inverting the
flask several times. Calculate the concentration in [micro]g/[micro]L
from the net gain in weight. When compound purity is assayed to be 96%
or greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.6.4 Transfer the stock standard solution into a Teflon-sealed
screw-cap bottle. Store at 4 [deg]C and protect from light.
6.6.5 All standards must be replaced after one month, or sooner if
comparison with check standards indicates a problem.
6.7 Secondary dilution standards--Using stock standard solutions,
prepare secondary dilution standards in methanol that contain the
compounds of interest, either singly or mixed together. The secondary
dilution standards should be prepared at concentrations such that the
aqueous calibration standards prepared in Section 7.3.1 or 7.4.1 will
bracket the working range of the analytical system. Secondary solution
standards must be stored with zero headspace and should be checked
frequently for signs of degradation or evaporation, especially just
prior to preparing calibration standards from them.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Assemble a purge and trap system that meets the specifications
in Section 5.2. Condition the trap overnight at 180 [deg]C by
backflushing with an inert gas flow of at least 20 mL/min. Condition the
trap for 10 min once daily prior to use.
7.2 Connect the purge and trap system to a gas chromatograph. The
gas chromatograph must be operated using temperature and flow rate
conditions equivalent to those given in Table 1. Calibrate the purge and
trap-gas chromatographic system using either the external standard
technique (Section 7.3) or the internal standard technique (Section
7.4).
7.3 External standard calibration procedure:
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter by carefully adding 20.0
[micro]L of one or more secondary dilution standards to 100, 500, or
1000 mL of reagent water. A 25-[micro]L syringe with a 0.006 in. ID
needle should be used for this operation. One of the external standards
should be at a concentration near, but above, the MDL (Table 1) and the
other concentrations should correspond to the expected range of
concentrations found in real samples or should define the working range
of the detector. These aqueous standards must be prepared fresh daily.
7.3.2 Analyze each calibration standard according to Section 10, and
tabulate peak height or area responses versus the concentration in the
standard. The results can be used to prepare a calibration curve for
each compound. Alternatively, if the ratio of response to concentration
(calibration factor) is a constant over the working range (<10% relative
standard deviation, RSD), linearity through the origin can be assumed
and the average ratio or calibration factor can be used in place of a
calibration curve.
7.4 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples. The compound, [alpha],[alpha],[alpha],-trifluorotoluene,
recommended as a surrogate spiking compound in Section 8.7 has been used
successfully as an internal standard.
7.4.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest as described in
Section 7.3.1.
7.4.2 Prepare a spiking solution containing each of the internal
standards using the procedures described in Sections 6.6 and 6.7. It is
recommended that the secondary dilution standard be prepared at a
concentration of 15 [micro]g/mL of each internal standard compound. The
addition of 10 [micro]l of this
[[Page 81]]
standard to 5.0 mL of sample or calibration standard would be equivalent
to 30 [micro]g/L.
7.4.3 Analyze each calibration standard according to Section 10,
adding 10 [micro]L of internal standard spiking solution directly to the
syringe (Section 10.4). Tabulate peak height or area responses against
concentration for each compound and internal standard, and calculate
response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard
Cs=Concentration of the parameter to be measured.
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.5 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of a QC check sample.
7.5.1 Prepare the QC check sample as described in Section 8.2.2.
7.5.2 Analyze the QC check sample according to Section 10.
7.5.3 For each parameter, compare the response (Q) with the
corresponding calibration acceptance criteria found in Table 2. If the
responses for all parameters of interest fall within the designated
ranges, analysis of actual samples can begin. If any individual Q falls
outside the range, a new calibration curve, calibration factor, or RF
must be prepared for that parameter according to Section 7.3 or 7.4.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The mimimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Section 10.1) to improve the separations or lower the cost of
measurements. Each time such a modification is made to the method, the
analyst is required to repeat the procedure in Section 8.2.
8.1.3 Each day, the analyst must analyze a reagent water blank to
demonstrate that interferences from the analytical system are under
control.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 10 [micro]g/
mL in methanol. The QC check sample concentrate must be obtained from
the U.S. Environmental Protection Agency, Environmental Monitoring and
Support Laboratory in Cincinnati, Ohio, if available. If not available
from that source, the QC check sample concentrate must be obtained from
another external source. If not available from either source above, the
QC check sample concentrate must be prepared by the laboratory using
stock standards prepared independently from those used for calibration.
8.2.2 Prepare a QC check sample to contain 20 [micro]g/L of each
parameter by adding 200 [micro]L of QC check sample concentrate to 100
mL of reagant water.
8.2.3 Analyze four 5-mL aliquots of the well-mixed QC check sample
according to Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
of interest using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively,
[[Page 82]]
found in Table 2. If s and X for all parameters of interest meet the
acceptance criteria, the system performance is acceptable and analysis
of actual samples can begin. If any individual s exceeds the precision
limit or any individual X falls outside the range for accuracy, the
system performance is unacceptable for that parameter.
Note: The large number of parameters in Table 2 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.3.
8.2.6.2 Beginning with Section 8.2.3, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compounds of interest beginning with Section 8.2.3.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 20 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.2 Analyze one 5-mL sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second 5-mL sample aliquot with 10
[micro]L of the QC check sample concentrate and analyze it to determine
the concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than 20 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 2, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 3, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 3,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T) 2.44(100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 10 [micro]L of QC
check sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent
water. The QC check standard needs only to contain the parameters that
failed criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P)
[[Page 83]]
and the standard deviation of the percent recovery (sp).
Express the accuracy assessment as a percent recovery interval from P-
2sp to P+2sp. If P=90% and sp=10%, for
example, the accuracy interval is expressed as 70-110%. Update the
accuracy assessment for each parameter on a regular basis (e.g. after
each five to ten new accuracy measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
8.7 The analyst should monitor both the performance of the
analytical system and the effectiveness of the method in dealing with
each sample matrix by spiking each sample, standard, and reagent water
blank with surrogate compounds (e.g. [alpha], [alpha], [alpha],-
trifluorotoluene) that encompass the range of the temperature program
used in this method. From stock standard solutions prepared as in
Section 6.6, add a volume to give 750 [micro]g of each surrogate to 45
mL of reagent water contained in a 50-mL volumetric flask, mix and
dilute to volume for a concentration of 15 mg/[micro]L. Add 10 [micro]L
of this surrogate spiking solution directly into the 5-mL syringe with
every sample and reference standard analyzed. Prepare a fresh surrogate
spiking solution on a weekly basis. If the internal standard calibration
procedure is being used, the surrogate compounds may be added directly
to the internal standard spiking solution (Section 7.4.2).
9. Sample Collection, Preservation, and Handling
9.1 The samples must be iced or refrigerated from the time of
collection until analysis. If the sample contains free or combined
chlorine, add sodium thiosulfate preservative (10 mg/40 mL is sufficient
for up to 5 ppm Cl2) to the empty sample bottle just prior to
shipping to the sampling site. EPA Method 330.4 or 330.5 may be used for
measurement of residual chlorine. \8\ Field test kits are available for
this purpose.
9.2 Collect about 500 mL of sample in a clean container. Adjust the
pH of the sample to about 2 by adding 1+1 HCl while stirring. Fill the
sample bottle in such a manner that no air bubbles pass through the
sample as the bottle is being filled. Seal the bottle so that no air
bubbles are entrapped in it. Maintain the hermetic seal on the sample
bottle until time of analysis.
9.3 All samples must be analyzed within 14 days of collection. \3\
10. Procedure
10.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are estimated retention times
and MDL that can be achieved under these conditions. An example of the
separations achieved by Column 1 is shown in Figure 6. Other packed
columns, chromatographic conditions, or detectors may be used if the
requirements of Section 8.2 are met.
10.2 Calibrate the system daily as described in Section 7.
10.3 Adjust the purge gas (nitrogen or helium) flow rate to 40 mL/
min. Attach the trap inlet to the purging device, and set the purge and
trap system to purge (Figure 3). Open the syringe valve located on the
purging device sample introduction needle.
10.4 Allow the sample to come to ambient temperature prior to
introducing it to the syringe. Remove the plunger from a 5-mL syringe
and attach a closed syringe valve. Open the sample bottle (or standard)
and carefully pour the sample into the syringe barrel to just short of
overflowing. Replace the syringe plunger and compress the sample. Open
the syringe valve and vent any residual air while adjusting the sample
volume to 5.0 mL. Since this process of taking an aliquot destroys the
validity of the sample for future analysis, the analyst should fill a
second syringe at this time to protect against possible loss of data.
Add 10.0 [micro]L of the surrogate spiking solution (Section 8.7) and
10.0 [micro]L of the internal standard spiking solution (Section 7.4.2),
if applicable, through the valve bore, then close the valve.
10.5 Attach the syringe-syringe valve assembly to the syringe valve
on the purging device. Open the syringe valves and inject the sample
into the purging chamber.
10.6 Close both valves and purge the sample for 12.0 0.1 min at ambient temperature.
10.7 After the 12-min purge time, disconnect the purging device from
the trap. Dry the trap by maintaining a flow of 40 mL/min of dry purge
gas through it for 6 min (Figure 4). If the purging device has no
provision for bypassing the purger for this step, a dry purger should be
inserted into the device to minimize moisture in the gas. Attach the
trap to the chromatograph, adjust the purge and trap system to the
desorb mode (Figure 5), and begin to temperature program the gas
chromatograph. Introduce the trapped materials to the GC column by
rapidly heating the trap to 180 [deg]C while backflushing the trap with
an inert gas between 20 and 60 mL/min for 4 min. If rapid heating of the
trap cannot be achieved, the GC column must be used as
[[Page 84]]
a secondary trap by cooling it to 30 [deg]C (subambient temperature, if
poor peak geometry and random retention time problems persist) instead
of the initial program temperature of 50 [deg]C.
10.8 While the trap is being desorbed into the gas chromatograph
column, empty the purging chamber using the sample introduction syringe.
Wash the chamber with two 5-mL flushes of reagent water.
10.9 After desorbing the sample for 4 min, recondition the trap by
returning the purge and trap system to the purge mode. Wait 15 s, then
close the syringe valve on the purging device to begin gas flow through
the trap. The trap temperature should be maintained at 180 [deg]C. After
approximately 7 min, turn off the trap heater and open the syringe valve
to stop the gas flow through the trap. When the trap is cool, the next
sample can be analyzed.
10.10 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
10.11 If the response for a peak exceeds the working range of the
system, prepare a dilution of the sample with reagent water from the
aliquot in the second syringe and reanalyze.
11. Calculations
11.1 Determine the concentration of individual compounds in the
sample.
11.1.1 If the external standard calibration procedure is used,
calculate the concentration of the parameter being measured from the
peak response using the calibration curve or calibration factor
determined in Section 7.3.2.
11.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.4.3 and Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.096
Equation 2
where:
As = Response for the parameter to be measured.
Ais = Response for the internal standard.
Cis = Concentration of the internal standard.
11.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
12. Method Performance
12.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \9\ Similar results
were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
12.2 This method has been demonstrated to be applicable for the
concentration range from the MDL to 100 x MDL. \9\ Direct aqueous
injection techniques should be used to measure concentration levels
above 1000 x MDL.
12.3 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 2.1 to 550 [micro]g/L. \9\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. Lichtenberg, J.J. ``Determining Volatile Organics at Microgram-
per-Litre-Levels by Gas Chromatography,'' Journal American Water Works
Association, 66, 739 (1974).
3. Bellar, T.A., and Lichtenberg, J.J. ``Semi-Automated Headspace
Analysis of Drinking Waters and Industrial Waters for Purgeable Volatile
Organic Compounds,'' Proceedings of Symposium on Measurement of Organic
Pollutants in Water and Wastewater. American Society for Testing and
Materials, STP 686, C.E. Van Hall, editor, 1978.
4. ``Carcinogens--Working with Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health.
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3. is two times the value 1.22
derived in this report.)
[[Page 85]]
8.``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Office of Research and Development,
Environmental Monitoring and Support Laboratory, Cincinnati, Ohio 45268.
March 1979.
9. ``EPA Method Study 25, Method 602, Purgeable Aromatics,'' EPA
600/4-84-042, National Technical Information Service, PB84-196682,
Springfield, Virginia 22161, May 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
---------------------- detection
Parameter limit
Column 1 Column 2 ([micro]g/
L)
------------------------------------------------------------------------
Benzene............................... 3.33 2.75 0.2
Toluene............................... 5.75 4.25 0.2
Ethylbenzene.......................... 8.25 6.25 0.2
Chlorobenzene......................... 9.17 8.02 0.2
1,4-Dichlorobenzene................... 16.8 16.2 0.3
1,3-Dichlorobenzene................... 18.2 15.0 0.4
1,2-Dichlorobenzene................... 25.9 19.4 0.4
------------------------------------------------------------------------
Column 1 conditions: Supelcoport (100/120 mesh) coated with 5% SP-1200/
1.75% Bentone-34 packed in a 6 ft x 0.085 in. ID stainless steel
column with helium carrier gas at 36 mL/min flow rate. Column
temperature held at 50 [deg]C for 2 min then programmed at 6 [deg]C/
min to 90 [deg]C for a final hold.
Column 2 conditions: Chromosorb W-AW (60/80 mesh) coated with 5% 1,2,3-
Tris(2-cyanoethyoxy)propane packed in a 6 ft x 0.085 in. ID stainless
steel column with helium carrier gas at 30 mL/min flow rate. Column
temperature held at 40 [deg]C for 2 min then programmed at 2 [deg]C/
min to 100 [deg]C for a final hold.
Table 2--Calibration and QC Acceptance Criteria--Method 602 \a\
----------------------------------------------------------------------------------------------------------------
Limit for Range for X
Range for Q s ([micro]g/ Range for
Parameter ([micro]g/ ([micro]g/ L) P, Ps(%)
L) L)
----------------------------------------------------------------------------------------------------------------
Benzene........................................................ 15.4-24.6 4.1 10.0-27.9 39-150
Chlorobenzene.................................................. 16.1-23.9 3.5 12.7-25.4 55-135
1,2-Dichlorobenzene............................................ 13.6-26.4 5.8 10.6-27.6 37-154
1,3-Dichlorobenzene............................................ 14.5-25.5 5.0 12.8-25.5 50-141
1,4-Dichlorobenzene............................................ 13.9-26.1 5.5 11.6-25.5 42-143
Ethylbenzene................................................... 12.6-27.4 6.7 10.0-28.2 32-160
Toluene........................................................ 15.5-24.5 4.0 11.2-27.7 46-148
----------------------------------------------------------------------------------------------------------------
Q=Concentration measured in QC check sample, in [micro]g/L (Section 7.5.3).
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
Ps, P=Percent recovery measured (Section 8.3.2, Section 8.4.2).
\a\ Criteria were calculated assuming a QC check sample concentration of 20 [micro]g/L.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the
limits for recovery have been broadened to assure applicability of the limits to concentrations below those
used to develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 602
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, s' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Benzene......................................................... 0.92C+0.57 0.09X+0.59 0.21X+0.56
Chlorobenzene................................................... 0.95C+0.02 0.09X+0.23 0.17X+0.10
1,2-Dichlorobenzene............................................. 0.93C+0.52 0.17X-0.04 0.22X+0.53
1,3-Dichlorobenzene............................................. 0.96C-0.05 0.15X-0.10 0.19X+0.09
1,4-Dichlorobenzene............................................. 0.93C-0.09 0.15X+0.28 0.20X+0.41
Ethylbenzene.................................................... 0.94C+0.31 0.17X+0.46 0.26X+0.23
Toluene......................................................... 0.94C+0.65 0.09X+0.48 0.18X+0.71
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
S'=Expected single analyst standard deviation of measurements at an average concentration found of X, in X
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the Concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 86]]
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[GRAPHIC] [TIFF OMITTED] TC02JY92.005
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[GRAPHIC] [TIFF OMITTED] TC02JY92.007
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Method 603--Acrolein and Acrylonitrile
1. Scope and Application
1.1 This method covers the determination of acrolein and
acrylonitrile. The following parameters may be determined by this
method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
Acrolein......................................... 34210 107-02-8
Acrylonitrile.................................... 34215 107-13-1
------------------------------------------------------------------------
1.2 This is a purge and trap gas chromatographic (GC) method
applicable to the determination of the compounds listed above in
municipal and industrial discharges as provided under 40 CFR 136.1. When
this method is used to analyze unfamiliar samples for either or both of
the compounds above, compound identifications should be supported by at
least one additional qualitative technique. This method describes
analytical conditions for a second gas chromatographic column that can
be used to confirm measurements made with the primary column. Method 624
provides gas chromatograph/mass spectrometer (GC/MS) conditions
appropriate for the qualitative and quantitative confirmation of results
for the parameters listed above, if used with the purge and trap
conditions described in this method.
1.3 The method detection limit (MDL, defined in Section 12.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the operation of a purge and trap system and a
gas chromatograph and in the interpretation of gas chromatograms. Each
analyst must demonstrate the ability to generate acceptable results with
this method using the procedure described in Section 8.2.
2. Summary of Method
2.1 An inert gas is bubbled through a 5-mL water sample contained in
a heated purging chamber. Acrolein and acrylonitrile are transferred
from the aqueous phase to the vapor phase. The vapor is swept through a
sorbent trap where the analytes are trapped. After the purge is
completed, the trap is heated and backflushed with the inert gas to
desorb the compound onto a gas chromatographic column. The gas
chromatograph is temperature programmed to separate the analytes which
are then detected with a flame ionization detector. \2,3\
2.2 The method provides an optional gas chromatographic column that
may be helpful in resolving the compounds of interest from the
interferences that may occur.
3. Interferences
3.1 Impurities in the purge gas and organic compound outgassing from
the plumbing of the trap account for the majority of contamination
problems. The analytical system must be demonstrated to be free from
contamination under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3. The use of non-Teflon
plastic tubing, non-Teflon thread sealants, or flow controllers with
rubber components in the purge and trap system should be avoided.
3.2 Samples can be contaminated by diffusion of volatile organics
through the septum seal into the sample during shipment and storage. A
field reagent blank prepared from reagent water and carried through the
sampling and handling protocol can serve as a check on such
contamination.
3.3 Contamination by carry-over can occur whenever high level and
low level samples are sequentially analyzed. To reduce carry-over, the
purging device and sample syringe must be rinsed between samples with
reagent water. Whenever an unusually concentrated sample is encountered,
it should be followed by an analysis of reagent water to check for cross
contamination. For samples containing large amounts of water-soluble
materials, suspended solids, high boiling compounds or high analyte
levels, it may be necessary to wash the purging device with a detergent
solution, rinse it with distilled water, and then dry it in an oven at
105 [deg]C between analyses. The trap and other parts of the system are
also subject to contamination, therefore, frequent bakeout and purging
of the entire system may be required.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this view point,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \4,6\ for
the information of the analyst.
[[Page 91]]
5. Apparatus and Materials
5.1 Sampling equipment, for discrete sampling.
5.1.1 Vial--25-mL capacity or larger, equipped with a screw cap with
a hole in the center (Pierce 13075 or equivalent). Detergent
wash, rinse with tap and distilled water, and dry at 105 [deg]C before
use.
5.1.2 Septum--Teflon-faced silicone (Pierce 12722 or
equivalent). Detergent wash, rinse with tap and distilled water and dry
at 105 [deg]C for 1 h before use.
5.2 Purge and trap system--The purge and trap system consists of
three separate pieces of equipment: a purging device, trap, and
desorber. Several complete systems are now commercially available.
5.2.1 The purging device must be designed to accept 5-mL, samples
with a water column at least 3 cm deep. The gaseous head space between
the water column and the trap must have a total volume of less than 15
mL. The purge gas must pass through the water column as finely divided
bubbles with a diameter of less than 3 mm at the origin. The purge gas
must be introduced no more than 5 mm from the base of the water column.
The purging device must be capable of being heated to 85 [deg]C within
3.0 min after transfer of the sample to the purging device and being
held at 85 2 [deg]C during the purge cycle. The
entire water column in the purging device must be heated. Design of this
modification to the standard purging device is optional, however, use of
a water bath is suggested.
5.2.1.1 Heating mantle--To be used to heat water bath.
5.2.1.2 Temperature controller--Equipped with thermocouple/sensor to
accurately control water bath temperature to 2
[deg]C. The purging device illustrated in Figure 1 meets these design
criteria.
5.2.2 The trap must be at least 25 cm long and have an inside
diameter of at least 0.105 in. The trap must be packed to contain 1.0 cm
of methyl silicone coated packing (Section 6.5.2) and 23 cm of 2,6-
diphenylene oxide polymer (Section 6.5.1). The minimum specifications
for the trap are illustrated in Figure 2.
5.2.3 The desorber must be capable of rapidly heating the trap to
180 [deg]C, The desorber illustrated in Figure 2 meets these design
criteria.
5.2.4 The purge and trap system may be assembled as a separate unit
as illustrated in Figure 3 or be coupled to a gas chromatograph.
5.3 pH paper--Narrow pH range, about 3.5 to 5.5 (Fisher Scientific
Short Range Alkacid No. 2, 14-837-2 or equivalent).
5.4 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, gases, detector, and strip-chart recorder. A data system is
recommended for measuring peak areas.
5.4.1 Column 1--10 ft long x 2 mm ID glass or stainless steel,
packed with Porapak-QS (80/100 mesh) or equivalent. This column was used
to develop the method performance statements in Section 12. Guidelines
for the use of alternate column packings are provided in Section 10.1.
5.4.2 Column 2--6 ft long x 0.1 in. ID glass or stainless steel,
packed with Chromosorb 101 (60/80 mesh) or equivalent.
5.4.3 Detector--Flame ionization detector. This type of detector has
proven effective in the analysis of wastewaters for the parameters
listed in the scope (Section 1.1), and was used to develop the method
performance statements in Section 12. Guidelines for the use of
alternate detectors are provided in Section 10.1.
5.5 Syringes--5-mL, glass hypodermic with Luerlok tip (two each).
5.6 Micro syringes--25-[micro]L, 0.006 in. ID needle.
5.7 Syringe valve--2-way, with Luer ends (three each).
5.8 Bottle--15-mL, screw-cap, with Teflon cap liner.
5.9 Balance--Analytical, capable of accurately weighing 0.0001 g.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.1.1 Reagent water can be generated by passing tap water through a
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
6.1.2 A water purification system (Millipore Super-Q or equivalent)
may be used to generate reagent water.
6.1.3 Regent water may also be prepared by boiling water for 15 min.
Subsequently, while maintaining the temperature at 90 [deg]C, bubble a
contaminant-free inert gas through the water for 1 h. While still hot,
transfer the water to a narrow mouth screw-cap bottle and seal with a
Teflon-lined septum and cap.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.4 Hydrochloric acid (1+1)--Slowly, add 50 mL of concentrated HCl
(ACS) to 50 mL of reagent water.
6.5 Trap Materials:
6.5.1 2,6-Diphenylene oxide polymer--Tenax (60/80 mesh),
chromatographic grade or equivalent.
6.5.2 Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh)
or equivalent.
[[Page 92]]
6.6 Stock standard solutions--Stock standard solutions may be
prepared from pure standard materials or purchased as certified
solutions. Prepare stock standard solutions in reagent water using
assayed liquids. Since acrolein and acrylonitrile are lachrymators,
primary dilutions of these compounds should be prepared in a hood. A
NIOSH/MESA approved toxic gas respirator should be used when the analyst
handles high concentrations of such materials.
6.6.1 Place about 9.8 mL of reagent water into a 10-mL ground glass
stoppered volumetric flask. For acrolein standards the reagent water
must be adjusted to pH 4 to 5. Weight the flask to the nearest 0.1 mg.
6.6.2 Using a 100-[micro]L syringe, immediately add two or more
drops of assayed reference material to the flask, then reweigh. Be sure
that the drops fall directly into the water without contacting the neck
of the flask.
6.6.3 Reweigh, dilute to volume, stopper, then mix by inverting the
flask several times. Calculate the concentration in [micro]g/[micro]L
from the net gain in weight. When compound purity is assayed to be 96%
or greater, the weight can be used without correction to calculate the
concentration of the stock staldard. Optionally, stock standard
solutions may be prepared using the pure standard material by
volumetrically measuring the appropriate amounts and determining the
weight of the material using the density of the material. Commercially
prepared stock standards may be used at any concentration if they are
certified by the manufactaurer or by an independent source.
6.6.4 Transfer the stock standard solution into a Teflon-sealed
screw-cap bottle. Store at 4 [deg]C and protect from light.
6.6.5 Prepare fresh standards daily.
6.7 Secondary dilution standards--Using stock standard solutions,
prepare secondary dilution standards in reagent water that contain the
compounds of interest, either singly or mixed together. The secondary
dilution standards should be prepared at concentrations such that the
aqueous calibration standards prepared in Section 7.3.1 or 7.4.1 will
bracket the working range of the analytical system. Secondary dilution
standards should be prepared daily and stored at 4 [deg]C.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Assemble a purge and trap system that meets the specifications
in Section 5.2. Condition the trap overnight at 180 [deg]C by
backflushing with an inert gas flow of at least 20 mL/min. Condition the
trap for 10 min once daily prior to use.
7.2 Connect the purge and trap system to a gas chromatograph. The
gas chromatograph must be operated using temperature and flow rate
conditions equivalent to those given in Table 1. Calibrate the purge and
trap-gas chromatographic system using either the external standard
technique (Section 7.3) or the internal standard technique (Section
7.4).
7.3 External standard calibration procedure:
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter by carefully adding 20.0
[micro]L of one or more secondary dilution standards to 100, 500, or
1000 mL of reagent water. A 25-[micro]L syringe with a 0.006 in. ID
needle should be used for this operation. One of the external standards
should be at a concentration near, but above, the MDL and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector. These standards must be prepared fresh daily.
7.3.2 Analyze each calibration standard according to Section 10, and
tabulate peak height or area responses versus the concentration of the
standard. The results can be used to prepare a calibration curve for
each compound. Alternatively, if the ratio of response to concentration
(calibration factor) is a constant over the working range (< 10%
relative standard deviation, RSD), linearity through the origin can be
assumed and the average ratio or calibration factor can be used in place
of a calibration curve.
7.4 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.4.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest as described in
Section 7.3.1.
7.4.2 Prepare a spiking solution containing each of the internal
standards using the procedures described in Sections 6.6 and 6.7. It is
recommended that the secondary dilution standard be prepared at a
concentration of 15 [micro]g/mL of each internal standard compound. The
addition of 10 [micro]L of this standard to 5.0 mL of sample or
calibration standard would be equivalent to 30 [micro]g/L.
7.4.3 Analyze each calibration standard according to Section 10,
adding 10 [micro]L of internal standard spiking solution directly to the
syringe (Section 10.4). Tabulate peak height or area responses against
concentration for each compound and internal standard, and calculate
response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
[[Page 93]]
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard.
Cs=Concentration of the parameter to be measured.
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.5 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of a QC check sample.
7.5.1 Prepare the QC check sample as described in Section 8.2.2.
7.5.2 Analyze the QC check sample according to Section 10.
7.5.3 For each parameter, compare the response (Q) with the
corresponding calibration acceptance criteria found in Table 2. If the
responses for all parameters of interest fall within the designated
ranges, analysis of actual samples can begin. If any individual Q falls
outside the range, a new calibration curve, calibration factor, or RF
must be prepared for that parameter according to Section 7.3 or 7.4.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Section 10.1) to improve the separations or lower the cost of
measurements. Each time such a modification is made to the method, the
analyst is required to repeat the procedure in Section 8.2.
8.1.3 Each day, the analyst must analyze a reagent water blank to
demonstrate that interferences from the analytical system are under
control.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 25 [micro]g/
mL in reagent water. The QC check sample concentrate must be obtained
from the U.S. Environmental Protection Agency, Environmental Monitoring
and Support Laboratory in Cincinnati, Ohio, if available. If not
available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Prepare a QC check sample to contain 50 [micro]g/L of each
parameter by adding 200 [micro]L of QC check sample concentrate to 100
mL of reagent water.
8.2.3 Analyze four 5-mL aliquots of the well-mixed QC check sample
according to Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 3. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If either s exceeds the precision limit or X falls
outside the range for accuracy, the system performance is unacceptable
for that parameter. Locate and correct the source of the problem and
repeat the test for each compound of interest.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to
[[Page 94]]
ten samples per month, at least one spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 50 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.2 Analyze one 5-mL sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second 5-mL sample aliquot with 10
[micro]L of the QC check sample concentrate and analyze it to determine
the concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 3. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 10 [micro]L of QC
check sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent
water. The QC check standard needs only to contain the parameters that
failed criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
3. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If P=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column or mass spectrometer
must be used. Whenever possible, the laboratory should analyze standard
reference materials and participate in relevant performance evaluation
studies.
9. Sample Collection, Preservation, and Handling
9.1 All samples must be iced or refrigerated from the time of
collection until analysis. If the sample contains free or combined
chlorine, add sodium thiosulfate preservative (10 mg/40 mL is sufficient
for up to 5 ppm Cl2) to the empty sample bottle just prior to
shipping to the sampling site. EPA Methods 330.4 and 330.5 may be used
for measurement of residual chlorine. \8\ Field test kits are available
for this purpose.
9.2 If acrolein is to be analyzed, collect about 500 mL of sample in
a clean glass container. Adjust the pH of the sample to 4 to 5 using
acid or base, measuring with narrow range pH paper. Samples for acrolein
analysis receiving no pH adjustment must be analyzed within 3 days of
sampling.
9.3 Grab samples must be collected in glass containers having a
total volume of at
[[Page 95]]
least 25 mL. Fill the sample bottle just to overflowing in such a manner
that no air bubbles pass through the sample as the bottle is being
filled. Seal the bottle so that no air bubbles are entrapped in it. If
preservative has been added, shake vigorously for 1 min. Maintain the
hermetic seal on the sample bottle until time of analysis.
9.4 All samples must be analyzed within 14 days of collection. \3\
10. Procedure
10.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are estimated retention times
and MDL that can be achieved under these conditions. An example of the
separations achieved by Column 1 is shown in Figure 5. Other packed
columns, chromatographic conditions, or detectors may be used if the
requirements of Section 8.2 are met.
10.2 Calibrate the system daily as described in Section 7.
10.3 Adjust the purge gas (nitrogen or helium) flow rate to 20 mL-
min. Attach the trap inlet to the purging device, and set the purge and
trap system to purge (Figure 3). Open the syringe valve located on the
purging device sample introduction needle.
10.4 Remove the plunger from a 5-mL syringe and attach a closed
syringe valve. Open the sample bottle (or standard) and carefully pour
the sample into the syringe barrel to just short of overflowing. Replace
the syringe plunger and compress the sample. Open the syringe valve and
vent any residual air while adjusting the sample volume to 5.0 mL. Since
this process of taking an aliquot destroys the validity of the sample
for future analysis, the analyst should fill a second syringe at this
time to protect against possible loss of data. Add 10.0 [micro]L of the
internal standard spiking solution (Section 7.4.2), if applicable,
through the valve bore then close the valve.
10.5 Attach the syringe-syringe valve assembly to the syringe valve
on the purging device. Open the syringe valves and inject the sample
into the purging chamber.
10.6 Close both valves and purge the sample for 15.0 0.1 min while heating at 85 2
[deg]C.
10.7 After the 15-min purge time, attach the trap to the
chromatograph, adjust the purge and trap system to the desorb mode
(Figure 4), and begin to temperature program the gas chromatograph.
Introduce the trapped materials to the GC column by rapidly heating the
trap to 180 [deg]C while backflushing the trap with an inert gas between
20 and 60 mL/min for 1.5 min.
10.8 While the trap is being desorbed into the gas chromatograph,
empty the purging chamber using the sample introduction syringe. Wash
the chamber with two 5-mL flushes of reagent water.
10.9 After desorbing the sample for 1.5 min, recondition the trap by
returning the purge and trap system to the purge mode. Wait 15 s then
close the syringe valve on the purging device to begin gas flow through
the trap. The trap temperature should be maintained at 210 [deg]C. After
approximately 7 min, turn off the trap heater and open the syringe valve
to stop the gas flow through the trap. When the trap is cool, the next
sample can be analyzed.
10.10 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
11. Calculations
11.1 Determine the concentration of individual compounds in the
sample.
11.1.1 If the external standard calibration procedure is used,
calculate the concentration of the parameter being measured from the
peak response using the calibration curve or calibration factor
determined in Section 7.3.2.
11.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.4.3 and Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.097
Equation 2
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard.
11.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
12. Method Performance
12.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \9\ The MDL
actually achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
[[Page 96]]
12.2 This method is recommended for the concentration range from the
MDL to 1,000xMDL. Direct aqueous injection techniques should be used to
measure concentration levels above 1,000xMDL.
12.3 In a single laboratory (Battelle-Columbus), the average
recoveries and standard deviations presented in Table 2 were obtained.
\9\ Seven replicate samples were analyzed at each spike level.
References
1. 40 CFR part 136, appendix B.
2. Bellar, T.A., and Lichtenberg, J.J. ``Determining Volatile
Organics at Microgram-per-Litre-Levels by Gas Chromatography,'' Journal
American Water Works Association, 66, 739 (1974).
3. ``Evaluate Test Procedures for Acrolein and Acrylonitrile,''
Special letter report for EPA Project 4719-A, U.S. Environmental
Protection Agency, Environmental Monitoring and Support Laboratory,
Cincinnati, Ohio 45268, 27 June 1979.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983).
8. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
9. ``Evaluation of Method 603 (Modified),'' EPA-600/4-84-ABC,
National Technical Information Service, PB84-, Springfield, Virginia
22161, Nov. 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
------------------------ detection
Parameter limit
Column 1 Column 2 ([micro]g/
L)
------------------------------------------------------------------------
Acrolein............................ 10.6 8.2 0.7
Acrylonitrile....................... 12.7 9.8 0.5
------------------------------------------------------------------------
Column 1 conditions: Porapak-QS (80/100 mesh) packed in a 10 ft x 2 mm
ID glass or stainless steel column with helium carrier gas at 30 mL/
min flow rate. Column temperature held isothermal at 110 [deg]C for
1.5 min (during desorption), then heated as rapidly as possible to 150
[deg]C and held for 20 min; column bakeout at 190 [deg]C for 10 min.
\9\
Column 2 conditions: Chromosorb 101 (60/80 mesh) packed in a 6 ft. x 0.1
in. ID glass or stainless steel column with helium carrier gas at 40
mL/min flow rate. Column temperature held isothermal at 80 [deg]C for
4 min, then programmed at 50 [deg]C/min to 120 [deg]C and held for 12
min.
Table 2--Single Laboratory Accuracy and Precision--Method 603
----------------------------------------------------------------------------------------------------------------
Spike Average Standard
Sample conc. recovery deviation Average
Parameter matrix ([micro]g/ ([micro]g/ ([micro]g/ percent
L) L) L) recovery
----------------------------------------------------------------------------------------------------------------
Acrolein............................................... RW 5.0 5.2 0.2 104
RW 50.0 51.4 0.7 103
POTW 5.0 4.0 0.2 80
POTW 50.0 44.4 0.8 89
IW 5.0 0.1 0.1 2
IW 100.0 9.3 1.1 9
Acrylonitrile.......................................... RW 5.0 4.2 0.2 84
RW 50.0 51.4 1.5 103
POTW 20.0 20.1 0.8 100
POTW 100.0 101.3 1.5 101
IW 10.0 9.1 0.8 91
IW 100.0 104.0 3.2 104
----------------------------------------------------------------------------------------------------------------
ARW=Reagent water.
APOTW=Prechlorination secondary effluent from a municipal sewage treatment plant.
AIW=Industrial wastewater containing an unidentified acrolein reactant.
Table 3--Calibration and QC Acceptance Criteria--Method 603 \a\
----------------------------------------------------------------------------------------------------------------
Limit for
Range for Q S Range for X Range for
Parameter ([micro]g/ ([micro]g/ ([micro]g/ P, Ps (%)
L) L) L)
----------------------------------------------------------------------------------------------------------------
Acrolein..................................................... 45.9-54.1 4.6 42.9-60.1 88-118
Acrylonitrile................................................ 41.2-58.8 9.9 33.1-69.9 71-135
----------------------------------------------------------------------------------------------------------------
\a\=Criteria were calculated assuming a QC check sample concentration of 50 [micro]g/L. \9\
Q=Concentration measured in QC check sample, in [micro]g/L (Section 7.5.3).
[[Page 97]]
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
[GRAPHIC] [TIFF OMITTED] TC02JY92.008
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[GRAPHIC] [TIFF OMITTED] TC02JY92.009
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[GRAPHIC] [TIFF OMITTED] TC02JY92.010
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[GRAPHIC] [TIFF OMITTED] TC02JY92.011
Method 604--Phenols
1. Scope and Application
1.1 This method covers the determination of phenol and certain
substituted phenols. The following parameters may be determined by this
method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
4-Chloro-3-methylphenol.......................... 34452 59-50-7
2--Chlorophenol.................................. 34586 95-57-8
2,4-Dichlorophenol............................... 34601 120-83-2
2,4-Dimethylphenol............................... 34606 105-67-9
2,4-Dinitrophenol................................ 34616 51-28-5
2-Methyl-4,6-dinitrophenol....................... 34657 534-52-1
2-Nitrophenol.................................... 34591 88-75-5
4-Nitrophenol.................................... 34646 100-02-7
Pentachlorophenol................................ 39032 87-86-5
Phenol........................................... 34694 108-95-2
2,4,6-Trichlorophenol............................ 34621 88-06-2
------------------------------------------------------------------------
1.2 This is a flame ionization detector gas chromatographic (FIDGC)
method applicable to the determination of the compounds listed above in
municipal and industrial discharges as provided under 40 CFR 136.1. When
this method is used to analyze unfamiliar samples for any or all of the
compounds above, compound identifications should be supported by at
least one additional qualitative technique. This method describes
analytical conditions for derivatization, cleanup, and electron capture
detector gas chromatography (ECDGC) that can be used to confirm
measurements made by FIDGC. Method 625 provides gas chromatograph/mass
spectrometer (GC/MS) conditions appropriate for the qualitative and
quantitative confirmation of results for all of the parameters listed
above, using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix. The MDL listed in Table 1 for each
parameter was achieved with a flame ionization detector (FID). The MDLs
that were achieved when the derivatization cleanup and electron capture
detector (ECD) were employed are presented in Table 2.
[[Page 101]]
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is acidified and
extracted with methylene chloride using a separatory funnel. The
methylene chloride extract is dried and exchanged to 2-propanol during
concentration to a volume of 10 mL or less. The extract is separated by
gas chromatography and the phenols are then measured with an FID. \2\
2.2 A preliminary sample wash under basic conditions can be employed
for samples having high general organic and organic base interferences.
2.3 The method also provides for a derivatization and column
chromatography cleanup procedure to aid in the elimination of
interferences. \2,3\ The derivatives are analyzed by ECDGC.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \4\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are
coextracted from the sample. The extent of matrix interferences will
vary considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
derivatization cleanup procedure in Section 12 can be used to overcome
many of these interferences, but unique samples may require additional
cleanup approaches to achieve the MDL listed in Tables 1 and 2.
3.3 The basic sample wash (Section 10.2) may cause significantly
reduced recovery of phenol and 2,4-dimethylphenol. The analyst must
recognize that results obtained under these conditions are minimum
concentrations.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
mothod has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \5,7\ for
the information of analyst.
4.2 Special care should be taken in handling pentafluorobenzyl
bromide, which is a lachrymator, and 18-crown-6-ether, which is highly
toxic.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be
[[Page 102]]
used. Before use, however, the compressible tubing should be thoroughly
rinsed with methanol, followed by repeated rinsings with distilled water
to minimize the potential for contamination of the sample. An
integrating flow meter is required to collect flow proportional
composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, 400 mm long x 19 mm ID,
with coarse frit filter disc.
5.2.3 Chromatographic column--100 mm long x 10 mm ID, with Teflon
stopcock.
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.8 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.9 Reaction flask--15 to 25-mL round bottom flask, with standard
tapered joint, fitted with a water-cooled condenser and U-shaped drying
tube containing granular calcium chloride.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2[deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighting 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, gases, detector, and strip-chart recorder. A data system is
recommended for measuring peak areas.
5.6.1 Column for underivatized phenols--1.8 m long x 2 mm ID glass,
packed with 1% SP-1240DA on Supelcoport (80/100 mesh) or equivalent.
This column was used to develop the method performance statements in
Section 14. Guidelines for the use of alternate column packings are
provided in Section 11.1.
5.6.2 Column for derivatized phenols--1.8 m long x 2 mm ID glass,
packed with 5% OV-17 on Chromosorb W-AW-DMCS (80/100 mesh) or
equivalent. This column has proven effective in the analysis of
wastewaters for derivatization products of the parameters listed in the
scope (Section 1.1), and was used to develop the method performance
statements in Section 14. Guidelines for the use of alternate column
packings are provided in Section 11.1.
5.6.3 Detectors--Flame ionization and electron capture detectors.
The FID is used when determining the parent phenols. The ECD is used
when determining the derivatized phenols. Guidelines for the use of
alternatve detectors are provided in Section 11.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.3 Sodium hydroxide solution (1 N)--Dissolve 4 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.4 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400[deg]C for 4 h in a shallow tray.
6.5 Sodium thiosulfate--(ACS) Granular.
6.6 Sulfuric acid (1+1)--Slowly, add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.7 Sulfuric acid (1 N)--Slowly, add 58 mL of
H2SO4 (ACS, sp. gr. 1.84) to reagent water and
dilute to 1 L.
6.8 Potassium carbonate--(ACS) Powdered.
6.9 Pentafluorobenzyl bromide ([alpha]-Bromopentafluorotoluene)--97%
minimum purity.
Note: This chemical is a lachrymator. (See Section 4.2.)
6.10 18-crown-6-ether (1,4,7,10,13,16-Hexaoxacyclooctadecane)--98%
minimum purity.
Note: This chemical is highly toxic.
6.11 Derivatization reagent--Add 1 mL of pentafluorobenzyl bromide
and 1 g of 18-crown-6-ether to a 50-mL volumetric flask and dilute to
volume with 2-propanol. Prepare fresh weekly. This operation should be
carried out in a hood. Store at 4 [deg]C and protect from light.
6.12 Acetone, hexane, methanol, methylene chloride, 2-propanol,
toluene--Pesticide quality or equivalent.
6.13 Silica gel--100/200 mesh, Davison, grade-923 or equivalent.
Activate at 130 [deg]C overnight and store in a desiccator.
6.14 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions may be prepared from pure standard materials or
purchased as certified solutions.
6.14.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in 2-propanol
[[Page 103]]
and dilute to volume in a 10-mL volumetric flask. Larger volumes can be
used at the convenience of the analyst. When compound purity is assayed
to be 96% or greater, the weight can be used without correction to
calculate the concentration of the stock standard. Commercially prepared
stock standards can be used at any concentration if they are certified
by the manufacturer or by an independent source.
6.14.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.14.3 Stock standard solutions must be replaced after six months,
or sooner if comparison with check standards indicates a problem.
6.15 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 To calibrate the FIDGC for the anaylsis of underivatized
phenols, establish gas chromatographic operating conditions equivalent
to those given in Table 1. The gas chromatographic system can be
calibrated using the external standard technique (Section 7.2) or the
internal standard technique (Section 7.3).
7.2 External standard calibration procedure for FIDGC:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with 2-propanol. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 2 to 5 [micro]l, analyze each calibration
standard according to Section 11 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure for FIDGC--To use this
approach, the analyst must select one or more internal standards that
are similar in analytical behavior to the compounds of interest. The
analyst must further demonstrate that the measurement of the internal
standard is not affected by method or matrix interferences. Because of
these limitations, no internal standard can be suggested that is
applicable to all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with 2-propanol. One of the standards should be at
a concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 11 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 To calibrate the ECDGC for the analysis of phenol derivatives,
establish gas chromatographic operating conditions equivalent to those
given in Table 2.
7.5.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with 2-propanol. One of the external standards should be at a
concentration near, but above, the MDL (Table 2) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
[[Page 104]]
7.5.2 Each time samples are to be derivatized, simultaneously treat
a 1-mL aliquot of each calibration standard as described in Section 12.
7.5.3 After derivatization, analyze 2 to 5 [micro]L of each column
eluate collected according to the method beginning in Section 12.8 and
tabulate peak height or area responses against the calculated equivalent
mass of underivatized phenol injected. The results can be used to
prepare a calibration curve for each compound.
7.6 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.6 and 11.1) to improve the separations or lower the cost of
measurements. Each time such a modification is made to the method, the
analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 100
[micro]g/mL in 2-propanol. The QC check sample concentrate must be
obtained from the U.S. Environmental Protection Agency, Environmental
Monitoring and Support Laboratory in Cincinnati, Ohio, if available. If
not available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
100 [micro]g/L by adding 1.00 mL of QC check sample concentrate to each
of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 3. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Talbe 3 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.2.
8.2.6.2 Beginning with Section 8.2.2, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem
[[Page 105]]
with the measurement system. If this occurs, locate and correct the
source of the problem and repeat the test for all compounds of interest
beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 100 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any,
or, if none, (2) the larger of either 5 times higher than the expected
background concentration or 100 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 3. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\8\ If spiking was performed at a concentration lower than 100 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 3, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 4, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 4,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T)2.44(100 S'/T)%. \8\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
3. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If P=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6. It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak
[[Page 106]]
on the chromatogram, confirmatory techniques such as gas chromatography
with a dissimilar column, specific element detector, or mass
spectrometer must be used. Whenever possible, the laboratory should
analyze standard reference materials and participate in relevant
performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \9\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction. Fill the sample bottles and, if
residual chlorine is present, add 80 mg of sodium thiosulfate per liter
of sample and mix well. EPA Methods 330.4 and 330.5 may be used for
measurement of residual chlorine. \10\ Field test kits are available for
this purpose.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of sample bottle for later
determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 For samples high in organic content, the analyst may solvent
wash the sample at basic pH as prescribed in Sections 10.2.1 and 10.2.2
to remove potential method interferences. Prolonged or exhaustive
contact with solvent during the wash may result in low recovery of some
of the phenols, notably phenol and 2,4-dimethylphenol. For relatively
clean samples, the wash should be omitted and the extraction, beginning
with Section 10.3, should be followed.
10.2.1 Adjust the pH of the sample to 12.0 or greater with sodium
hydroxide solution.
10.2.2 Add 60 mL of methylene chloride to the sample by shaking the
funnel for 1 min with periodic venting to release excess pressure.
Discard the solvent layer. The wash can be repeated up to two additional
times if significant color is being removed.
10.3 Adjust the sample to a pH of 1 to 2 with sulfuric acid.
10.4 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.5 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.6 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.7 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.8 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.9 Increase the temperature of the hot water bath to 95 to 100
[deg]C. Remove the Synder column and rinse the flask and its lower joint
into the concentrator tube with 1 to 2 mL of 2-propanol. A 5-mL syringe
is recommended for this operation. Attach a two-ball micro-Snyder column
to the concentrator tube and prewet the column by adding about 0.5 mL of
2-propanol to the top. Place the micro-K-D apparatus on the water bath
so that the concentrator tube is partially immersed in the hot water.
Adjust the vertical position of the apparatus and the water temperature
as required to complete concentration in 5 to 10 min. At the proper rate
of distillation the balls of the column will actively chatter but the
chambers will
[[Page 107]]
not flood. When the apparent volume of liquid reaches 2.5 mL, remove the
K-D apparatus and allow it to drain and cool for at least 10 min. Add an
additional 2 mL of 2-propanol through the top of the micro-Snyder column
and resume concentrating as before. When the apparent volume of liquid
reaches 0.5 mL, remove the K-D apparatus and allow it to drain and cool
for at least 10 min.
10.10 Remove the micro-Snyder column and rinse its lower joint into
the concentrator tube with a minimum amount of 2-propanol. Adjust the
extract volume to 1.0 mL. Stopper the concentrator tube and store
refrigerated at 4 [deg]C if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial. If the sample
extract requires no further cleanup, proceed with FIDGC analysis
(Section 11). If the sample requires further cleanup, proceed to Section
12.
10.11 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Flame Ionization Detector Gas Chromatography
11.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. An example of the
separations achieved by this column is shown in Figure 1. Other packed
or capillary (open-tubular) columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
11.2 Calibrate the system daily as described in Section 7.
11.3 If the internal standard calibration procedure is used, the
internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatograph.
11.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \11\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, and
the resulting peak size in area or peak height units.
11.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
may be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
11.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
11.7 If the measurement of the peak response is prevented by the
presence of interferences, an alternative gas chromatographic procedure
is required. Section 12 describes a derivatization and column
chromatographic procedure which has been tested and found to be a
practical means of analyzing phenols in complex extracts.
12. Derivatization and Electron Capture Detector Gas Chromatography
12.1 Pipet a 1.0-mL aliquot of the 2-propanol solution of standard
or sample extract into a glass reaction vial. Add 1.0 mL of derivatizing
reagent (Section 6.11). This amount of reagent is sufficient to
derivatize a solution whose total phenolic content does not exceed 0.3
mg/mL.
12.2 Add about 3 mg of potassium carbonate to the solution and shake
gently.
12.3 Cap the mixture and heat it for 4 h at 80 [deg]C in a hot water
bath.
12.4 Remove the solution from the hot water bath and allow it to
cool.
12.5 Add 10 mL of hexane to the reaction flask and shake vigorously
for 1 min. Add 3.0 mL of distilled, deionized water to the reaction
flask and shake for 2 min. Decant a portion of the organic layer into a
concentrator tube and cap with a glass stopper.
12.6 Place 4.0 g of silica gel into a chromatographic column. Tap
the column to settle the silica gel and add about 2 g of anhydrous
sodium sulfate to the top.
12.7 Preelute the column with 6 mL of hexane. Discard the eluate and
just prior to exposure of the sodium sulfate layer to the air, pipet
onto the column 2.0 mL of the hexane solution (Section 12.5) that
contains the derivatized sample or standard. Elute the column with 10.0
mL of hexane and discard the eluate. Elute the column, in order, with:
10.0 mL of 15% toluene in hexane (Fraction 1); 10.0 mL of 40% toluene in
hexane (Fraction 2); 10.0 mL of 75% toluene in hexane (Fraction 3); and
10.0 mL of 15% 2-propanol in toluene (Fraction 4). All elution mixtures
are prepared on a volume: volume basis. Elution patterns for the
phenolic derivatives are shown in Table 2. Fractions may be combined as
desired, depending upon the specific phenols of interest or level of
interferences.
12.8 Analyze the fractions by ECDGC. Table 2 summarizes the
recommended operating conditions for the gas chromatograph. Included in
this table are retention times and MDL that can be achieved under these
conditions. An example of the separations achieved by this column is
shown in Figure 2.
[[Page 108]]
12.9 Calibrate the system daily with a minimum of three aliquots of
calibration standards, containing each of the phenols of interest that
are derivatized according to Section 7.5.
12.10 Inject 2 to 5 [micro]L of the column fractions into the gas
chromatograph using the solvent-flush technique. Smaller (1.0 [micro]L)
volumes can be injected if automatic devices are employed. Record the
volume injected to the nearest 0.05 [micro]L, and the resulting peak
size in area or peak height units. If the peak response exceeds the
linear range of the system, dilute the extract and reanalyze.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample analyzed by FIDGC (without derivatization) as indicated below.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.098
Equation 2
where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([micro]L).
Vt=Volume of total extract ([micro]L).
Vs=Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.099
Equation 3
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract
([micro]g).
Vo=Volume of water extracted (L).
13.2 Determine the concentration of individual compounds in the
sample analyzed by derivatization and ECDGC according to Equation 4.
[GRAPHIC] [TIFF OMITTED] TC15NO91.100
Equation 4
where:
A=Mass of underivatized phenol represented by area of peak in sample
chromatogram, determined from calibration curve in Section 7.5.3 (ng).
Vi=Volume of eluate injected ([micro]L).
Vt=Total volume of column eluate or combined fractions from
which Vi was taken ([micro]L).
Vs=Volume of water extracted in Section 10.10 (mL).
B=Total volume of hexane added in Section 12.5 (mL).
C=Volume of hexane sample solution added to cleanup column in Section
12.7 (mL).
D=Total volume of 2-propanol extract prior to derivatization (mL).
E=Volume of 2-propanol extract carried through derivatization in Section
12.1 (mL).
13.3 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Tables 1 and 2 were obtained using reagent water. \12\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
as six concentrations over the range 12 to 450 [micro]g/L. \13\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships for a flame ionization detector are
presented in Table 4.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Phenols in Industrial and Municipal
Wastewaters,'' EPA 600/4-84-ABC, National Technical Information Service,
PBXYZ, Springfield, Virginia 22161, November 1984.
3. Kawahara, F. K. ``Microdetermination of Derivatives of Phenols
and Mercaptans by Means of Electron Capture Gas Chromatography,''
Analytical Chemistry, 40, 1009 (1968).
4. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American
[[Page 109]]
Society for Testing and Materials, Philadelphia.
5. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
6. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
7. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
8. Provost, L. P., and Elder, R. S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
9. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
10. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methmds for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
11. Burke, J. A. ``Gas Chromatography for Pesticide Residue
Analysis; Some Practical Aspects,'' Journal of the Association of
Official Analytical Chemists, 48, 1037 (1965).
12. ``Development of Detection Limits, EPA Method 604, Phenols,''
Special letter report for EPA Contract 68-03-2625, U.S. Environmental
Protection Agency, Environmental Monitoring and Support Laboratory,
Cincinnati, Ohio 45268.
13. ``EPA Method Study 14 Method 604-Phenols,'' EPA 600/4-84-044,
National Technical Information Service, PB84-196211, Springfield,
Virginia 22161, May 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Method
Retention detection
Parameter time (min) limit
([micro]g/L)
------------------------------------------------------------------------
2-Chlorophenol................................ 1.70 0.31
2-Nitrophenol................................. 2.00 0.45
Phenol........................................ 3.01 0.14
2,4-Dimethylphenol............................ 4.03 0.32
2,4-Dichlorophenol............................ 4.30 0.39
2,4,6-Trichlorophenol......................... 6.05 0.64
4-Chloro-3-methylphenol....................... 7.50 0.36
2,4-Dinitrophenol............................. 10.00 13.0
2-Methyl-4,6-dinitrophenol.................... 10.24 16.0
Pentachlorophenol............................. 12.42 7.4
4-Nitrophenol................................. 24.25 2.8
------------------------------------------------------------------------
Column conditions: Supelcoport (80/100 mesh) coated with 1% SP-1240DA
packed in a 1.8 m long x 2 mm ID glass column with nitrogen carrier
gas at 30 mL/min flow rate. Column temperature was 80 [deg]C at
injection, programmed immediately at 8 [deg]C/min to 150 [deg]C final
temperature. MDL were determined with an FID.
Table 2--Silica Gel Fractionation and Electron Capture Gas Chromatography of PFBB Derivatives
----------------------------------------------------------------------------------------------------------------
Percent recovery by Method
fraction \a\ Retention detection
Parent compound ---------------------------- time limit
(min) ([micro]g/
1 2 3 4 L)
----------------------------------------------------------------------------------------------------------------
2-Chlorophenol............................................... ..... 90 1 ..... 3.3 0.58
2-Nitrophenol................................................ ..... ..... 9 90 9.1 0.77
Phenol....................................................... ..... 90 10 ..... 1.8 2.2
2,4-Dimethylphenol........................................... ..... 95 7 ..... 2.9 0.63
2,4-Dichlorophenol........................................... ..... 95 1 ..... 5.8 0.68
2,4,6-Trichlorophenol........................................ 50 50 ..... ..... 7.0 0.58
4-Chloro-3-methylphenol...................................... ..... 84 14 ..... 4.8 1.8
Pentachlorophenol............................................ 75 20 ..... ..... 28.8 0.59
4-Nitrophenol................................................ ..... ..... 1 90 14.0 0.70
----------------------------------------------------------------------------------------------------------------
Column conditions: Chromosorb W-AW-DMCS (80/100 mesh) coated with 5% OV-17 packed in a 1.8 m long x 2.0 mm ID
glass column with 5% methane/95% argon carrier gas at 30 mL/min flow rate. Column temperature held isothermal
at 200 [deg]C. MDL were determined with an ECD.
\a\ Eluant composition:
Fraction 1--15% toluene in hexane.
Fraction 2--40% toluene in hexane.
Fraction 3--75% toluene in hexane.
Fraction 4--15% 2-propanol in toluene.
[[Page 110]]
Table 3--QC Acceptance Criteria--Method 604
----------------------------------------------------------------------------------------------------------------
Limit for Range for X
Test conc. s ([micro]g/ Range for
Parameter ([micro]g/ ([micro]g/ L) P, Ps
L) L) (percent)
----------------------------------------------------------------------------------------------------------------
4-Chloro-3-methylphenol....................................... 100 16.6 56.7-113.4 49-122
2-Chlorophenol................................................ 100 27.0 54.1-110.2 38-126
2,4-Dichlorophenol............................................ 100 25.1 59.7-103.3 44-119
2,4-Dimethylphenol............................................ 100 33.3 50.4-100.0 24-118
4,6-Dinitro-2-methylphenol.................................... 100 25.0 42.4-123.6 30-136
2,4-Dinitrophenol............................................. 100 36.0 31.7-125.1 12-145
2-Nitrophenol................................................. 100 22.5 56.6-103.8 43-117
4-Nitrophenol................................................. 100 19.0 22.7-100.0 13-110
Pentachlorophenol............................................. 100 32.4 56.7-113.5 36-134
Phenol........................................................ 100 14.1 32.4-100.0 23-108
2,4,6-Trichlorophenol......................................... 100 16.6 60.8-110.4 53-119
----------------------------------------------------------------------------------------------------------------
s--Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X--Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps--Percent recovery measured (Section 8.3.2, Section 8.4.2).
Note: These criteria are based directly upon the method performance data in Table 4. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 4.
Table 4--Method Accuracy and Precision as Functions of Concentration--Method 604
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single Analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
4-Chloro-3-methylphenol................................ 0.87C-1.97 0.11X-0.21 0.16X+1.41
2-Chlorophenol......................................... 0.83C-0.84 0.18X+0.20 0.21X+0.75
2,4-Dichlorophenol..................................... 0.81C+0.48 0.17X-0.02 0.18X+0.62
2,4-Dimethylphenol..................................... 0.62C-1.64 0.30X-0.89 0.25X+0.48
4,6-Dinitro-2-methylphenol............................. 0.84C-1.01 0.15X+1.25 0.19X+5.85
2,4-Dinitrophenol...................................... 0.80C-1.58 0.27X-1.15 0.29X+4.51
2-Nitrophenol.......................................... 0.81C-0.76 0.15X+0.44 0.14X+3.84
4-Nitrophenol.......................................... 0.46C+0.18 0.17X+2.43 0.19X+4.79
Pentachlorophenol...................................... 0.83C+2.07 0.22X-0.58 0.23X+0.57
Phenol................................................. 0.43C+0.11 0.20X-0.88 0.17X+0.77
2,4,6-Trichlorophenol.................................. 0.86C-0.40 0.10X+0.53 0.13X+2.40
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 111]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.012
[[Page 112]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.013
Method 605--Benzidines
1. Scope and Application
1.1 This method covers the determination of certain benzidines. The
following parameters can be determined by this method:
------------------------------------------------------------------------
Parameter Storet No CAS No.
------------------------------------------------------------------------
Benzidine..................................... 39120 92-87-5
3,3'-Dichlorobenzidine........................ 34631 91-94-1
------------------------------------------------------------------------
1.2 This is a high performance liquid chromatography (HPLC) method
applicable to the determination of the compounds listed above in
municipal and industrial discharges as provided under 40 CFR 136.1. When
this method is used to analyze unfamiliar samples for the compounds
above, identifications should be supported by at least one additional
qualitative technique. This method describes electrochemical conditions
at a second potential which can be used to confirm measurements made
with this method. Method 625 provides gas chromatograph/mass
spectrometer (GC/MS) conditions appropriate for the qualitative and
quantitative confirmation of results for the parameters listed above,
using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is
[[Page 113]]
listed in Table 1. The MDL for a specific wastewater may differ from
those listed, depending upon the nature of the interferences in the
sample matrix.
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the use of HPLC instrumentation and in the
interpretation of liquid chromatograms. Each analyst must demonstrate
the ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with chloroform using liquid-liquid extractions in a separatory funnel.
The chloroform extract is extracted with acid. The acid extract is then
neutralized and extracted with chloroform. The final chloroform extract
is exchanged to methanol while being concentrated using a rotary
evaporator. The extract is mixed with buffer and separated by HPLC. The
benzidine compounds are measured with an electrochemical detector. \2\
2.2 The acid back-extraction acts as a general purpose cleanup to
aid in the elimination of interferences.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in chromatograms. All of
these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials may not be eliminated
by this treatment. Solvent rinses with acetone and pesticide quality
hexane may be substituted for the muffle furnace heating. Volumetric
ware should not be heated in a muffle furnace. After drying and cooling,
glassware should be sealed and stored in a clean environment to prevent
any accumulation of dust or other contaminants. Store inverted or capped
with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedures that are inherent in the extraction step are used to
overcome many of these interferences, but unique samples may require
additional cleanup approaches to achieve the MDL listed in Table 1.
3.3 Some dye plant effluents contain large amounts of components
with retention times closed to benzidine. In these cases, it has been
found useful to reduce the electrode potential in order to eliminate
interferences and still detect benzidine. (See Section 12.7.)
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health harzard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \4,6\ for
the information of the analyst.
4.2 The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: benzidine and 3,3'-dichlorobenzidine. Primary standards of
these toxic compounds should be prepared in a hood. A NIOSH/MESA
approved toxic gas respirator should be worn when the analyst handles
high concentrations of these toxic compounds.
4.3 Exposure to chloroform should be minimized by performing all
extractions and extract concentrations in a hood or other well-
ventiliated area.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene
[[Page 114]]
chloride, and dried before use to minimize contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4[deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested):
5.2.1 Separatory funnels--2000, 1000, and 250-mL, with Teflon
stopcock.
5.2.2 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.3 Rotary evaporator.
5.2.4 Flasks--Round bottom, 100-mL, with 24/40 joints.
5.2.5 Centrifuge tubes--Conical, graduated, with Teflon-lined screw
caps.
5.2.6 Pipettes--Pasteur, with bulbs.
5.3 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.4 High performance liquid chromatograph (HPLC)--An analytical
system complete with column supplies, high pressure syringes, detector,
and compatible recorder. A data system is recommended for measuring peak
areas and retention times.
5.4.1 Solvent delivery system--With pulse damper, Altex 110A or
equivalent.
5.4.2 Injection valve (optional)--Waters U6K or equivalent.
5.4.3 Electrochemical detector--Bioanalytical Systems LC-2A with
glassy carbon electrode, or equivalent. This detector has proven
effective in the analysis of wastewaters for the parameters listed in
the scope (Section 1.1), and was used to develop the method performance
statements in Section 14. Guidelines for the use of alternate detectors
are provided in Section 12.1.
5.4.4 Electrode polishing kit--Princeton Applied Research Model 9320
or equivalent.
5.4.5 Column--Lichrosorb RP-2, 5 micron particle diameter, in a 25
cm x 4.6 mm ID stainless steel column. This column was used to develop
the method performance statements in Section 14. Guidelines for the use
of alternate column packings are provided in Section 12.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium hydroxide solution (5 N)--Dissolve 20 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.3 Sodium hydroxide solution (1 M)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 1 L.
6.4 Sodium thiosulfate--(ACS) Granular.
6.5 Sodium tribasic phosphate (0.4 M)--Dissolve 160 g of trisodium
phosphate decahydrate (ACS) in reagent water and dilute to 1 L.
6.6 Sulfuric acid (1+1)--Slowly, add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.7 Sulfuric acid (1 M)--Slowly, add 58 mL of
H2SO4 (ACS, sp. gr. 1.84) to reagent water and
dilute to 1 L.
6.8 Acetate buffer (0.1 M, pH 4.7)--Dissolve 5.8 mL of glacial
acetic acid (ACS) and 13.6 g of sodium acetate trihydrate (ACS) in
reagent water which has been purified by filtration through a RO-4
Millipore System or equivalent and dilute to 1 L.
6.9 Acetonitrile, chloroform (preserved with 1% ethanol), methanol--
Pesticide quality or equivalent.
6.10 Mobile phase--Place equal volumes of filtered acetonitrile
(Millipore type FH filter or equivalent) and filtered acetate buffer
(Millipore type GS filter or equivalent) in a narrow-mouth, glass
container and mix thoroughly. Prepare fresh weekly. Degas daily by
sonicating under vacuum, by heating and stirring, or by purging with
helium.
6.11 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions may be prepared from pure standard materials or
purchased as certified solutions.
6.11.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in methanol and dilute
to volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.11.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.11.3 Stock standard solutions must be replaced after six months,
or sooner if comparison with check standards indicates a problem.
6.12 Quality control check sample concentrate--See Section 8.2.1.
[[Page 115]]
7. Calibration
7.1 Establish chromatographic operating conditions equivalent to
those given in Table 1. The HPLC system can be calibrated using the
external standard technique (Section 7.2) or the internal standard
technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with mobile phase. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using syringe injections of 5 to 25 [micro]L or a constant
volume injection loop, analyze each calibration standard according to
Section 12 and tabulate peak height or area responses against the mass
injected. The results can be used to prepare a calibration curve for
each compound. Alternatively, if the ratio of response to amount
injected (calibration factor) is a constant over the working range (<10%
relative standard deviation, RSD), linearity through the origin can be
assumed and the average ratio or calibration factor can be used in place
of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with mobile phase. One of the standards should be
at a concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using syringe injections of 5 to 25 [micro]L or a constant
volume injection loop, analyze each calibration standard according to
Section 12 and tabulate peak height or area responses against
concentration for each compound and internal standard. Calculate
response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound. If serious loss of
response occurs, polish the electrode and recalibrate.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.9, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
[[Page 116]]
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing benzidine and/or 3,3'-dichlorobenzidine at a concentration of
50 [micro]g/mL each in methanol. The QC check sample concentrate must be
obtained from the U.S. Environmental Protection Agency, Environmental
Monitoring and Support Laboratory in Cincinnati, Ohio, if available. If
not available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
50 [micro]g/L by adding 1.00 mL of QC check sample concentrate to each
of four 1-L-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter. Locate and correct the
source of the problem and repeat the test for all parameters of interest
beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 50 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or 50 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than 50 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 2, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 3, substituting
[[Page 117]]
the spike concentration (T) for C; (2) calculate overall precision (S')
using the equation in Table 3, substituting X' for X; (3) calculate the
range for recovery at the spike concentration as (100 X'/T)2.44(100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Sections 8.2.1 or 8.3.2) to 1 L of reagent water.
The QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If P=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as HPLC with a dissimilar column, gas chromatography, or mass
spectrometer must be used. Whenever possible, the laboratory should
analyze standard reference materials and participate in relevant
performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \8\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4[deg]C and stored
in the dark from the time of collection until extraction. Both benzidine
and 3,3'-dichlorobenzidine are easily oxidized. Fill the sample bottles
and, if residual chlorine is present, add 80 mg of sodium thiosulfate
per liter of sample and mix well. EPA Methods 330.4 and 330.5 may be
used for measurement of residual chlorine. \9\ Field test kits are
available for this purpose. After mixing, adjust the pH of the sample to
a range of 2 to 7 with sulfuric acid.
9.3 If 1,2-diphenylhydrazine is likely to be present, adjust the pH
of the sample to 4.0 0.2 to prevent rearrangement
to benzidine.
9.4 All samples must be extracted within 7 days of collection.
Extracts may be held up to 7 days before analysis, if stored under an
inert (oxidant free) atmosphere. \2\ The extract should be protected
from light.
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel. Check the pH of the sample with wide-range pH paper
and adjust to within the range of 6.5 to 7.5 with sodium hydroxide
solution or sulfuric acid.
10.2 Add 100 mL of chloroform to the sample bottle, seal, and shake
30 s to rinse the inner surface. (Caution: Handle chloroform in a well
ventilated area.) Transfer the solvent to the separatory funnel and
extract the sample by shaking the funnel for 2 min with periodic venting
to release excess pressure. Allow the organic layer to separate from the
water phase for a minimum of 10 min. If the emulsion interface between
layers is more than one-third the volume of the solvent layer, the
analyst must employ mechanical techniques to complete the phase
separation. The optimum technique depends upon the sample, but may
include stirring,
[[Page 118]]
filtration of the emulsion through glass wool, centrifugation, or other
physical methods. Collect the chloroform extract in a 250-mL separatory
funnel.
10.3 Add a 50-mL volume of chloroform to the sample bottle and
repeat the extraction procedure a second time, combining the extracts in
the separatory funnel. Perform a third extraction in the same manner.
10.4 Separate and discard any aqueous layer remaining in the 250-mL
separatory funnel after combining the organic extracts. Add 25 mL of 1 M
sulfuric acid and extract the sample by shaking the funnel for 2 min.
Transfer the aqueous layer to a 250-mL beaker. Extract with two
additional 25-mL portions of 1 M sulfuric acid and combine the acid
extracts in the beaker.
10.5 Place a stirbar in the 250-mL beaker and stir the acid extract
while carefully adding 5 mL of 0.4 M sodium tribasic phosphate. While
monitoring with a pH meter, neutralize the extract to a pH between 6 and
7 by dropwise addition of 5 N sodium hydroxide solution while stirring
the solution vigorously. Approximately 25 to 30 mL of 5 N sodium
hydroxide solution will be required and it should be added over at least
a 2-min period. Do not allow the sample pH to exceed 8.
10.6 Transfer the neutralized extract into a 250-mL separatory
funnel. Add 30 mL of chloroform and shake the funnel for 2 min. Allow
the phases to separate, and transfer the organic layer to a second 250-
mL separatory funnel.
10.7 Extract the aqueous layer with two additional 20-mL aliquots of
chloroform as before. Combine the extracts in the 250-mL separatory
funnel.
10.8 Add 20 mL of reagent water to the combined organic layers and
shake for 30 s.
10.9 Transfer the organic extract into a 100-mL round bottom flask.
Add 20 mL of methanol and concentrate to 5 mL with a rotary evaporator
at reduced pressure and 35 [deg]C. An aspirator is recommended for use
as the source of vacuum. Chill the receiver with ice. This operation
requires approximately 10 min. Other concentration techniques may be
used if the requirements of Section 8.2 are met.
10.10 Using a 9-in. Pasteur pipette, transfer the extract to a 15-
mL, conical, screw-cap centrifuge tube. Rinse the flask, including the
entire side wall, with 2-mL portions of methanol and combine with the
original extract.
10.11 Carefully concentrate the extract to 0.5 mL using a gentle
stream of nitrogen while heating in a 30 [deg]C water bath. Dilute to 2
mL with methanol, reconcentrate to 1 mL, and dilute to 5 mL with acetate
buffer. Mix the extract thoroughly. Cap the centrifuge tube and store
refrigerated and protected from light if further processing will not be
performed immediately. If the extract will be stored longer than two
days, it should be transferred to a Teflon-sealed screw-cap vial. If the
sample extract requires no further cleanup, proceed with HPLC analysis
(Section 12). If the sample requires further cleanup, proceed to Section
11.
10.12 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1,000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst first must demonstrate that the requirements of
Section 8.2 can be met using the method as revised to incorporate the
cleanup procedure.
12. High Performance Liquid Chromatography
12.1 Table 1 summarizes the recommended operating conditions for the
HPLC. Included in this table are retention times, capacity factors, and
MDL that can be achieved under these conditions. An example of the
separations achieved by this HPLC column is shown in Figure 1. Other
HPLC columns, chromatographic conditions, or detectors may be used if
the requirements of Section 8.2 are met. When the HPLC is idle, it is
advisable to maintain a 0.1 mL/min flow through the column to prolong
column life.
12.2 Calibrate the system daily as described in Section 7.
12.3 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the instrument.
12.4 Inject 5 to 25 [micro]L of the sample extract or standard into
the HPLC. If constant volume injection loops are not used, record the
volume injected to the nearest 0.05 [micro]L, and the resulting peak
size in area or peak height units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract with mobile phase and reanalyze.
[[Page 119]]
12.7 If the measurement of the peak response for benzidine is
prevented by the presence of interferences, reduce the electrode
potential to +0.6 V and reanalyze. If the benzidine peak is still
obscured by interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.101
Equation 2
where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([micro]L).
Vt=Volume of total extract ([micro]L).
Vs=Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.102
Equation 3
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract
([micro]g).
Vo=Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \10\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 7xMDL to 3000xMDL. \10\
14.3 This method was tested by 17 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 1.0 to 70 [micro]g/L. \11\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Benzidines in Industrial and Muncipal
Wastewaters,'' EPA 600/4-82-022, National Technical Information Service,
PB82-196320, Springfield, Virginia 22161, April 1982.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
9. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
10. ``EPA Method Study 15, Method 605 (Benzidines),'' EPA 600/4-84-
062, National Technical Information Service, PB84-211176, Springfield,
Virginia 22161, June 1984.
11. ``EPA Method Validation Study 15, Method 605 (Benzidines),''
Report for EPA Contract 68-03-2624 (In preparation).
[[Page 120]]
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Method
Column detection
Parameter Retention capacity limit
time (min) factor (k') ([micro]g/
L)
------------------------------------------------------------------------
Benzidine........................ 6.1 1.44 0.08
3,3'-Dichlorobenzidine........... 12.1 3.84 0.13
------------------------------------------------------------------------
HPLC Column conditions: Lichrosorb RP-2, 5 micron particle size, in a 25
cmx4.6 mm ID stainless steel column. Mobile Phase: 0.8 mL/min of 50%
acetonitrile/50% 0.1M pH 4.7 acetate buffer. The MDL were determined
using an electrochemical detector operated at +0.8 V.
Table 2--QC Acceptance Criteria--Method 605
----------------------------------------------------------------------------------------------------------------
Limit for Range for
Test conc. s X Range for
Parameter ([micro]g/ ([micro]g/ ([micro]g/ P, Ps
L) L) L) (percent)
----------------------------------------------------------------------------------------------------------------
Benzidine........................................................ 50 18.7 9.1-61.0 D-140
3.3'-Dichlorobenzidine........................................... 50 23.6 18.7-50.0 5-128
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 605
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, precision, sr' precision, S'
X'([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Benzidine....................................................... 0.70C+0.06 0.28X+0.19 0.40X+0.18
3,3'-Dichlorobenzidine.......................................... 0.66C+0.23 0.39X-0.05 0.38X+0.02
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 121]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.014
[[Page 122]]
Method 606--Phthalate Ester
1. Scope and Application
1.1 This method covers the determination of certain phthalate
esters. The following parameters can be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
Bis(2-ethylhexyl) phthalate........................ 39100 117-81-7
Butyl benzyl phthalate............................. 34292 85-68-7
Di-n-butyl phthalate............................... 39110 84-74-2
Diethyl phthalate.................................. 34336 84-66-2
Dimethyl phthalate................................. 34341 131-11-3
Di-n-octyl phthalate............................... 34596 117-84-0
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of the compounds listed above in municipal and industrial
discharges as provided under 40 CFR 136.1. When this method is used to
analyze unfamiliar samples for any or all of the compounds above,
compound identifications should be supported by at least one additional
qualitative technique. This method describes analytical conditions for a
second gas chromatographic column that can be used to confirm
measurements made with the primary column. Method 625 provides gas
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the
qualitative and quantitative confirmation of results for all of the
parameters listed above, using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 The sample extraction and concentration steps in this method are
essentially the same as in Methods 608, 609, 611, and 612. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. The analyst is
allowed the latitude, under Section 12, to select chromatographic
conditions appropriate for the simultaneous measurement of combinations
of these parameters.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and exchanged to hexane during concentration
to a volume of 10 mL or less. The extract is separated by gas
chromatography and the phthalate esters are then measured with an
electron capture detector. \2\
2.2 Analysis for phthalates is especially complicated by their
ubiquitous occurrence in the environment. The method provides Florisil
and alumina column cleanup procedures to aid in the elimination of
interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Phthalate esters are contaminants in many products commonly
found in the laboratory. It is particularly important to avoid the use
of plastics because phthalates are commonly used as plasticizers and are
easily extracted from plastic materials. Serious phthalate contamination
can result at any time, if consistent quality control is not practiced.
Great care must be experienced to prevent such contamination. Exhaustive
cleanup of reagents and glassware may be required to eliminate
background phthalate contamination. \4,5\
[[Page 123]]
3.3 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedures in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified \6,8\ for
the information of the analyst.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only).
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Chromatographic column--300 mm long x 10 mm ID, with Teflon
stopcock and coarse frit filter disc at bottom (Kontes K-420540-0213 or
equivalent).
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.8 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with gas
chromatograph suitable for on-column injection and all required
accessories including syringes, analytical columns, gases, detector, and
strip-chart recorder. A data system is recommended for measuring peak
areas.
5.6.1 Column 1--1.8 m long x 4 mm ID glass, packed with 1.5% SP-
2250/1.95% SP-2401 Supelcoport (100/120 mesh) or equivalent. This column
was used to develop the method performance statemelts in Section 14.
Guidelines for the use of alternate column packings are provided in
Section 12.1.
5.6.2 Column 2--1.8 m long x 4 mm ID glass, packed with 3% OV-1 on
Supelcoport (100/120 mesh) or equivalent.
5.6.3 Detector--Electron capture detector. This detector has proven
effective in the analysis of wastewaters for the parameters listed in
the scope (Section 1.1), and was used to develop the method performance
statements in Section 14. Guidelines for the use of alternate detectors
are provided in Section 12.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Acetone, hexane, isooctane, methylene chloride, methanol--
Pesticide quality or equivalent.
6.3 Ethyl ether--nanograde, redistilled in glass if necessary.
6.3.1 Ethyl ether must be shown to be free of peroxides before it is
used as indicated by
[[Page 124]]
EM Laboratories Quant test strips. (Available from Scientific Products
Co., Cat. No. P1126-8, and other suppliers.)
6.3.2 Procedures recommended for removal of peroxides are provided
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative
must be added to each liter of ether.
6.4 Sodium sulfate--(ACS) Granular, anhydrous. Several levels of
purification may be required in order to reduce background phthalate
levels to an acceptable level: 1) Heat 4 h at 400 [deg]C in a shallow
tray, 2) Heat 16 h at 450 to 500 [deg]C in a shallow tray, 3) Soxhlet
extract with methylene chloride for 48 h.
6.5 Florisil--PR grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in the dark in glass containers with ground glass
stoppers or foil-lined screw caps. To prepare for use, place 100 g of
Florisil into a 500-mL beaker and heat for approximately 16 h at 40
[deg]C. After heating transfer to a 500-mL reagent bottle. Tightly seal
and cool to room temperature. When cool add 3 mL of reagent water. Mix
thoroughly by shaking or rolling for 10 min and let it stand for at
least 2 h. Keep the bottle sealed tightly.
6.6 Alumina--Neutral activity Super I, W200 series (ICN Life
Sciences Group, No. 404583). To prepare for use, place 100 g of alumina
into a 500-mL beaker and heat for approximately 16 h at 400 [deg]C.
After heating transfer to a 500-mL reagent bottle. Tightly seal and cool
to room temperature. When cool add 3 mL of reagent water. Mix thoroughly
by shaking or rolling for 10 min and let it stand for at least 2 h. Keep
the bottle sealed tightly.
6.7 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.7.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in isooctane and dilute
to volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.7.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.7.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with check standards indicates a problem.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatograph operating conditions equivalent to
those given in Table 1. The gas chromatographic system can be calibrated
using the external standard technique (Section 7.2) or the internal
standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepared calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with isooctane. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flash. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with isooctane. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
[[Page 125]]
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality contrml (QC) check sample concentrate is required
containing each parameter of interest at the following concentrations in
acetone: butyl benzyl phthalate, 10 [micro]g/mL; bis(2-ethylhexyl)
phthalate, 50 [micro]g/mL; di-n-octyl phthalate, 50 [micro]g/mL; any
other phthlate, 25 [micro]g/mL. The QC check sample concentrate must be
obtained from the U.S. Environmental Protection Agancy, Environmental
Monitoring and Support Laboratory in Cincinnati, Ohio, if available. If
not available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Using a pipet, prepare QC check samples at the test
concentrations shown in Table 2 by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively,
[[Page 126]]
found in Table 2. If s and X for all parameters of interest meet the
acceptance criteria, the system performance is acceptable and analysis
of actual samples can begin. If any individual s exceeds the precision
limit or any individual X falls outside the range for accuracy, the
system performance is unacceptable for that parameter. Locate and
correct the source of the problem and repeat the test for all parameters
of interest beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at the test concentration in Section 8.2.2 or 1 to 5
times higher than the background concentration determined in Section
8.3.2, whichever concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or the test concentration in Section 8.2.2.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\9\ If spiking was performed at a concentration lower than the test
concentration in Section 8.2.2, the analyst must use either the QC
acceptance criteria in Table 2, or optional QC acceptance criteria
calculated for the specific spike concentration. To calculate optional
acceptance criteria for the recovery of a parameter: (1) Calculate
accuracy (X') using the equation in Table 3, substituting the spike
concentration (T) for C; (2) calculate overall precision (S') using the
equation in Table 3, substituting X' for X; (3) calculate the range for
recovery at the spike concentration as (100 X'/T)2.44(100 S'/T)%. \9\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If P=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
[[Page 127]]
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \10\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phrase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentrator
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.7 Increase the temperature of the hot water bath to about 80
[deg]C. Momentarily remove the Snyder column, add 50 mL of hexane and a
new boiling chip, and reattach the Snyder column. Concentrate the
extract as in Section 10.6, except use hexane to prewet the column. The
elapsed time of concentration should be 5 to 10 min.
10.8 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL
syringe is recommended for this operation. Adjust the extract volume to
10 mL. Stopper the concentrator tube and store refrigerated if further
processing will not be performed immediately. If the extract will be
stored longer than two days, it should be transferred to a Teflon-sealed
screw-cap vial. If the sample extract requires no further cleanup,
proceed with gas chromatographic analysis (Section 12). If the sample
requires further cleanup, proceed to Section 11.
10.9 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11. Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use either procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of
[[Page 128]]
Section 8.2 can be met using the method as revised to incorporate the
cleanup procedure.
11.2 If the entire extract is to be cleaned up by one of the
following procedures, it must be concentrated to 2.0 mL. To the
concentrator tube in Section 10.8, add a clean boiling chip and attach a
two-ball micro-Snyder column. Prewet the column by adding about 0.5 mL
of hexane to the top. Place the micro-K-D apparatus on a hot water bath
(80 [deg]C) so that the concentrator tube is partially immersed in the
hot water. Adjust the vertical position of the apparatus and the water
temperature as required to complete the concentration in 5 to 10 min. At
the proper rate of distillation the balls of the column will actively
chatter but the chambers will not flood. When the apparent volume of
liquid reaches about 0.5 mL, remove the K-D apparatus and allow it to
drain and cool for at least 10 min. Remove the micro-Snyder column and
rinse its lower joint into the concentrator tube with 0.2 mL of hexane.
Adjust the final volume to 2.0 mL and proceed with one of the following
cleanup procedures.
11.3 Florisil column cleanup for phthalate esters:
11.3.1 Place 10 g of Florisil into a chromatographic column. Tap the
column to settle the Florisil and add 1 cm of anhydrous sodium sulfate
to the top.
11.3.2 Preelute the column with 40 mL of hexane. The rate for all
elutions should be about 2 mL/min. Discard the eluate and just prior to
exposure of the sodium sulfate layer to the air, quantitatively transfer
the 2-mL sample extract onto the column using an additional 2 mL of
hexane to complete the transfer. Just prior to exposure of the sodium
sulfate layer to the air, add 40 mL of hexane and continue the elution
of the column. Discard this hexane eluate.
11.3.3 Next, elute the column with 100 mL of 20% ethyl ether in
hexane (V/V) into a 500-mL K-D flask equipped with a 10-mL concentrator
tube. Concentrate the collected fraction as in Section 10.6. No solvent
exchange is necessary. Adjust the volume of the cleaned up extract to 10
mL in the concentrator tube and analyze by gas chromatography (Section
12).
11.4 Alumina column cleanup for phthalate esters:
11.4.1 Place 10 g of alumina into a chromatographic column. Tap the
column to settle the alumina and add 1 cm of anhydrous sodium sulfate to
the top.
11.4.2 Preelute the column with 40 mL of hexane. The rate for all
elutions should be about 2 mL/min. Discard the eluate and just prior to
exposure of the sodium sulfate layer to the air, quantitatively transfer
the 2-mL sample extract onto the column using an additional 2 mL of
hexane to complete the transfer. Just prior to exposure of the sodium
sulfate layer to the air, add 35 mL of hexane and continue the elution
of the column. Discard this hexane eluate.
11.4.3 Next, elute the column with 140 mL of 20% ethyl ether in
hexane (V/V) into a 500-mL K-D flask equipped with a 10-mL concentrator
type. Concentrate the collected fraction as in Section 10.6. No solvent
exchange is necessary. Adjust the volume of the cleaned up extract to 10
mL in the concentrator tube and analyze by gas chromatography (Section
12).
12. Gas Chromatography
12.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Examples of the separations
achieved by Column 1 are shown in Figures 1 and 2. Other packed or
capillary (open-tubular) columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
12.2 Calibrate the system daily as described in Section 7.
12.3 If the internal standard calibration procedure is being used,
the internal staldard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatograph.
12.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas-chromatograph using the solvent-flush technique. \11\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, and
the resulting peak size in area or peak height units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration
[[Page 129]]
factor determined in Section 7.2.2. The concentration in the sample can
be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.103
Equation 2
where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([micro]L).
Vt=Volume of total extract ([micro]L).
Vs=Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.104
Equation 3
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract
([micro]g).
Vo=Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \12\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 5 x MDL to 1000 x MDL with the following
exceptions: dimethyl and diethyl phthalate recoveries at 1000 x MDL were
low (70%); bis-2-ethylhexyl and di-n-octyl phthalate recoveries at 5 x
MDL were low (60%). \12\
14.3 This method was tested by 16 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 0.7 to 106 [micro]g/L. \13\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Phthalates in Industrial and Muncipal
Wastewaters,'' EPA 600/4-81-063, National Technical Information Service,
PB81-232167, Springfield, Virginia 22161, July 1981.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
4. Giam, C.S., Chan, H.S., and Nef, G.S. ``Sensitive Method for
Determination of Phthalate Ester Plasticizers in Open-Ocean Biota
Samples,'' Analytical Chemistry, 47, 2225 (1975).
5. Giam, C.S., and Chan, H.S. ``Control of Blanks in the Analysis of
Phthalates in Air and Ocean Biota Samples,'' U.S. National Bureau of
Standards, Special Publication 442, pp. 701-708, 1976.
6. ``Carcinogens--Working with Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
7. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
8. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
9. Provost L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
10. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
11. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
12. ``Method Detection Limit and Analytical Curve Studies, EPA
Methods 606, 607, and 608,'' Special letter report for EPA Contract 68-
03-2606, U.S. Environmental Protection Agency, Environmental Monitoring
and Support Laboratory, Cincinnati, Ohio 45268, June 1980.
13. ``EPA Method Study 16 Method 606 (Phthalate Esters),'' EPA 600/
4-84-056, National Technical Information Service, PB84-211275,
Springfield, Virginia 22161, June 1984.
[[Page 130]]
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
---------------------------- detection
Parameter limit
Column 1 Column 2 ([micro]g/L)
------------------------------------------------------------------------
Dimethyl phthalate............ 2.03 0.95 0.29
Diethyl phthalate............. 2.82 1.27 0.49
Di-n-butyl phthalate.......... 8.65 3.50 0.36
Butyl benzyl phthalate........ \a\ 6.94 \a\ 5.11 0.34
Bis(2-ethylhexyl) phthalate... \a\ 8.92 \a\ 10.5 2.0
Di-n-octyl phthalate.......... \a\ 16.2 \a\ 18.0 3.0
------------------------------------------------------------------------
Column 1 conditions: Supelcoport (100/120 mesh) coated with 1.5% SP-2250/
1.95% SP-2401 packed in a 1.8 m long x 4 mm ID glass column with 5%
methane/95% argon carrier gas at 60 mL/min flow rate. Column
temperature held isothermal at 180[deg]C, except where otherwise
indicated.
Column 2 conditions: Supelcoport (100/120 mesh) coated with 3% OV-1
packed in a 1.8 m long x 4 mm ID glass column with 5% methane/95%
argon carrier gas at 60 mL/min flow rate. Column temperature held
isothermal at 200 [deg]C, except where otherwise indicated.
\a\ 220 [deg]C column temperature.
Table 2--QC Acceptance Criteria--Method 606
----------------------------------------------------------------------------------------------------------------
Limit for Range for
Test conc. s X Range for
Parameter ([micro]g/ ([micro]g/ ([micro]g/ P, Ps
L) L) L) (percent)
----------------------------------------------------------------------------------------------------------------
Bis(2-ethylhexyl) phthalate...................................... 50 38.4 1.2-55.9 D-158
Butyl benzyl phthalate........................................... 10 4.2 5.7-11.0 30-136
Di-n-butyl phthalate............................................. 25 8.9 10.3-29.6 23-136
Diethyl phthalate................................................ 25 9.0 1.9-33.4 D-149
Dimethyl phathalate.............................................. 25 9.5 1.3-35.5 D-156
Di-n-octyl phthalate............................................. 50 13.4 D-50.0 D-114
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 606
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Bis(2-ethylhexyl) phthalate..................................... 0.53C+2.02 0.80X-2.54 0.73X-0.17
Butyl benzyl phthalate.......................................... 0.82C+0.13 0.26X+0.04 0.25X+0.07
Di-n-butyl phthalate............................................ 0.79C+0.17 0.23X+0.20 0.29X+0.06
Diethyl phthalate............................................... 0.70C+0.13 0.27X+0.05 0.45X+0.11
Dimethyl phthalate.............................................. 0.73C+0.17 0.26X+0.14 0.44X+0.31
Di-n-octyl phthalate............................................ 0.35C-0.71 0.38X+0.71 0.62X+0.34
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 131]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.015
[[Page 132]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.016
[[Page 133]]
Method 607--Nitrosamines
1. Scope and Application
1.1 This method covers the determination of certain nitrosamines.
The following parameters can be determined by this method:
------------------------------------------------------------------------
Parameter Storet No. CAS No.
------------------------------------------------------------------------
N-Nitrosodimethylamine........................ 34438 62-75-9
N-Nitrosodiphenylamine........................ 34433 86-30-6
N-Nitrosodi-n-propylamine..................... 34428 621-64-7
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of the parameters listed above in municipal and industrial
discharges as provided under 40 CFR 136.1. When this method is used to
analyze unfamiliar samples for any or all of the compmunds above,
compound identifications should be supported by at least one additional
qualitative technique. This method describes analytical conditimns for a
second gas chromatographic column that can be used to confirm
measurements made with the primary column. Method 625 provides gas
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the
qualitative and quantitative confirmation of results for N-nitrosodi-n-
propylamine. In order to confirm the presence of N-nitrosodiphenylamine,
the cleanup procedure specified in Section 11.3 or 11.4 must be used. In
order to confirm the presence of N-nitrosodimethylamine by GC/MS, Column
1 of this method must be substituted for the column recommended in
Method 625. Confirmation of these parameters using GC-high resolution
mass spectrometry or a Thermal Energy Analyzer is also recommended.
\1,2\
1.3 The method detection limit (MDL, defined in Section 14.1) \3\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.5 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is washed with dilute hydrochloric acid to remove free
amines, dried, and concentrated to a volume of 10 mL or less. After the
extract has been exchanged to methanol, it is separated by gas
chromatography and the parameters are then measured with a nitrogen-
phosphorus detector. \4\
2.2 The method provides Florisil and alumina column cleanup
procedures to separate diphenylamine from the nitrosamines and to aid in
the elimination of interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \5\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Solvent rinses with acetone and pesticide quality
hexane may be substituted for the muffle furnace heating. Volumetric
ware should not be heated in a muffle furnace. After drying and cooling,
glassware should be sealed and stored in a clean environment to prevent
any accumulation of dust or other contaminants. Store inverted or capped
with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedures in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
3.3 N-Nitrosodiphenylamine is reported 6-9 to undergo
transnitrosation reactions. Care must be exercised in the heating or
concentrating of solutions containing this compound in the presence of
reactive amines.
3.4 The sensitive and selective Thermal Energy Analyzer and the
reductive Hall detector may be used in place of the nitrogen-phosphorus
detector when interferences are encountered. The Thermal Energy Analyzer
offers the highest selectivity of the non-MS detectors.
[[Page 134]]
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified
10-12 for the information of the analyst.
4.2 These nitrosamines are known carcinogens, 13-17
therefore, utmost care must be exercised in the handling of these
materials. Nitrosamine reference standards and standard solutions should
be handled and prepared in a ventilated glove box within a properly
ventilated room.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flowmeter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnels--2-L and 250-mL, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.4 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.5 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.6 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.7 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.8 Chromatographic column--Approximately 400 mm long x 22 mm ID,
with Teflon stopcock and coarse frit filter disc at bottom (Kontes K-
420540-0234 or equivalent), for use in Florisil column cleanup
procedure.
5.2.9 Chromatographic column--Approximately 300 mm long x 10 mm ID,
with Teflon stopcock and coarse frit filter disc at bottom (Kontes K-
420540-0213 or equivalent), for use in alumina column cleanup procedure.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with gas
chromatograph suitable for on-column injection and all required
accessories including syringes, analytical columns, gases, detector, and
strip-chart recorder. A data system is recommended for measuring peak
areas.
5.6.1 Column 1--1.8 m long x 4 mm ID glass, packed with 10% Carbowax
20 M/2% KOH on Chromosorb W-AW (80/100 mesh) or equivalent. This column
was used to develop the method performance statements in Section 14.
Guidelines for the use of alternate column packings are provided in
Section 12.2.
5.6.2 Column 2--1.8 m long x 4 mm ID glass, packed with 10% SP-2250
on Supel-coport (100/120 mesh) or equivalent.
5.6.3 Detector--Nitrogen-phosphorus, reductive Hall, or Thermal
Energy Analyzer detector. \1,2\ These detectors have proven effective in
the analysis of wastewaters for the parameters listed in the scope
(Section 1.1). A nitrogen-phosphorus detector was used to develop the
method performance statements in Section 14. Guidelines for the use of
alternate detectors are provided in Section 12.2.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 ml.
[[Page 135]]
6.3 Sodium thiosulfate--(ACS) Granular.
6.4 Sulfuric acid (1+1)--Slowly, add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.5 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.6 Hydrochloric acid (1+9)--Add one volume of concentrated HCl
(ACS) to nine volumes of reagent water.
6.7 Acetone, methanol, methylene chloride, pentane--Pesticide
quality or equivalent.
6.8 Ethyl ether--Nanograde, redistilled in glass if necessary.
6.8.1 Ethyl ether must be shown to be free of peroxides before it is
used as indicated by EM Laboratories Quant test strips. (Available from
Scientific Products Co., Cat No. P1126-8, and other suppliers.)
6.8.2 Procedures recommended for removal of peroxides are provided
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative
must be added to each liter of ether.
6.9 Florisil--PR grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in the dark in glass containers with ground glass
stoppers or foil-lined screw caps. Before use, activate each batch at
least 16 h at 130 [deg]C in a foil-covered glass container and allow to
cool.
6.10 Alumina--Basic activity Super I, W200 series (ICN Life Sciences
Group, No. 404571, or equivalent). To prepare for use, place 100 g of
alumina into a 500-mL reagent bottle and add 2 mL of reagent water. Mix
the alumina preparation thoroughly by shaking or rolling for 10 min and
let it stand for at least 2 h. The preparation should be homogeneous
before use. Keep the bottle sealed tightly to ensure proper activity.
6.11 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.11.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in methanol and dilute
to volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.11.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.11.3 Stock standard solutions must be replaced after six months,
or sooner if comparison with check standards indicates a problem.
6.12 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatographic operating conditions equivalent to
those given in Table 1. The gas chromatographic system can be calibrated
using the external standard technique (Section 7.2) or the internal
standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with methanol. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with methanol. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
[[Page 136]]
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
RF = (As)(Cis (Ais)(Cs)
Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.2) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 20 [micro]g/
mL in methanol. The QC check sample concentrate must be obtained from
the U.S. Environmental Protection Agency, Environmental Monitoring and
Support Laboratory in Cincinnati, Ohio, if available. If not available
from that source, the QC check sample concentrate must be obtained from
another external source. If not available from either source above, the
QC check sample concentrate must be prepared by the laboratory using
stock standards prepared independently from those used for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
20 [micro]g/L by adding 1.00 mL of QC check sample concentrate to each
of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If
[[Page 137]]
any individual s exceeds the precision limit or any individual X falls
outside the range for accuracy, the system performance is unacceptable
for that parameter. Locate and correct the source of the problem and
repeat the test for all parameters of interest beginning with Section
8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 20 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or 20 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were caluclated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\18\ If spiking was performed at a concentration lower than 20 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 2, or
optional QC acceptance criteria caluclated for the specific spike
concentration. To calculate optional acceptance crtieria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 3, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 3,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T) 2.44(100 S'/T)%. \18\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If P=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of
[[Page 138]]
the samples. Field duplicates may be analyzed to assess the precision of
the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \19\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction. Fill the sample bottles and, if
residual chlorine is present, add 80 mg of sodium thiosulfate per liter
of sample and mix well. EPA Methods 330.4 and 330.5 may be used for
measurement of residual chlorine. \20\ Field test kits are available for
this purpose. If N-nitrosodiphenylamine is to be determined, adjust the
sample pH to 7 to 10 with sodium hydroxide solution or sulfuric acid.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \4\
9.4 Nitrosamines are known to be light sensitive. \7\ Samples should
be stored in amber or foil-wrapped bottles in order to minimize
photolytic decomposition.
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel. Check the pH of the sample with wide-range pH paper
and adjust to within the range of 5 to 9 with sodium hydroxide solution
or sulfuric acid.
10.2 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2 min
with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Add 10 mL of hydrochloric acid to the combined extracts and
shake for 2 min. Allow the layers to separate. Pour the combined extract
through a solvent-rinsed drying column containing about 10 cm of
anhydrous sodium sulfate, and collect the extract in the K-D
concentrator. Rinse the Erlenmeyer flask and column with 20 to 30 mL of
methylene chloride to complete the quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65[deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.7 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of methylene chloride. A
5-mL syringe is recommended for this operation. Stopper the concentrator
tube and store refrigerated if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial. If N-
nitrosodiphenylamine is to be measured by gas chromatography, the
analyst must first use a cleanup column to eliminate diphenylamine
interference (Section 11). If N-nitrosodiphenylamine is of no interest,
the analyst may proceed directly with gas chromatographic analysis
(Section 12).
10.8 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-
mL graduated cylinder. Record the sample volume to the nearest 5 mL.
[[Page 139]]
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use either procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the method as revised
to incorporate the cleanup procedure. Diphenylamine, if present in the
original sample extract, must be separated from the nitrosamines if N-
nitrosodiphenylamine is to be determined by this method.
11.2 If the entire extract is to be cleaned up by one of the
following procedures, it must be concentrated to 2.0 mL. To the
concentrator tube in Section 10.7, add a clean boiling chip and attach a
two-ball micro-Snyder column. Prewet the column by adding about 0.5 mL
of methylene chloride to the top. Place the micr-K-D apparatus on a hot
water bath (60 to 65 [deg]C) so that the concentrator tube is partially
immersed in the hot water. Adjust the vertical position of the apparatus
and the water temperature as required to complete the concentration in 5
to 10 min. At the proper rate of distillation the balls of the column
will actively chatter but the chambers will not flood. When the apparent
volume of liquid reaches about 0.5 mL, remove the K-D apparatus and
allow it to drain and cool for at least 10 min. Remove the micro-Snyder
column and rinse its lower joint into the concentrator tube with 0.2 mL
of methylene chloride. Adjust the final volume to 2.0 mL and proceed
with one of the following cleanup procedures.
11.3 Florisil column cleanup for nitrosamines:
11.3.1 Place 22 g of activated Florisil into a 22-mm ID
chromatographic column. Tap the column to settle the Florisil and add
about 5 mm of anhydrous sodium sulfate to the top.
11.3.2 Preelute the column with 40 mL of ethyl ether/pentane
(15+85)(V/V). Discard the eluate and just prior to exposure of the
sodium sulfate layer to the air, quantitatively transfer the 2-mL sample
extract onto the column using an additional 2 mL of pentane to complete
the transfer.
11.3.3 Elute the column with 90 mL of ethyl ether/pentane (15+85)(V/
V) and discard the eluate. This fraction will contain the diphenylamine,
if it is present in the extract.
11.3.4 Next, elute the column with 100 mL of acetone/ethyl ether
(5+95)(V/V) into a 500-mL K-D flask equipped with a 10-mL concentrator
tube. This fraction will contain all of the nitrosamines listed in the
scope of the method.
11.3.5 Add 15 mL of methanol to the collected fraction and
concentrate as in Section 10.6, except use pentane to prewet the column
and set the water bath at 70 to 75 [deg]C. When the apparatus is cool,
remove the Snyder column and rinse the flask and its lower joint into
the concentrator tube with 1 to 2 mL of pentane. Analyze by gas
chromatography (Section 12).
11.4 Alumina column cleanup for nitrosamines:
11.4.1 Place 12 g of the alumina preparation (Section 6.10) into a
10-mm ID chromatographic column. Tap the column to settle the alumina
and add 1 to 2 cm of anhydrous sodium sulfate to the top.
11.4.2 Preelute the column with 10 mL of ethyl ether/pentane
(3+7)(V/V). Discard the eluate (about 2 mL) and just prior to exposure
of the sodium sulfate layer to the air, quantitatively transfer the 2 mL
sample extract onto the column using an additional 2 mL of pentane to
complete the transfer.
11.4.3 Just prior to exposure of the sodium sulfate layer to the
air, add 70 mL of ethyl ether/pentane (3+7)(V/V). Discard the first 10
mL of eluate. Collect the remainder of the eluate in a 500-mL K-D flask
equipped with a 10 mL concentrator tube. This fraction contains N-
nitrosodiphenylamine and probably a small amount of N-nitrosodi-n-
propylamine.
11.4.4 Next, elute the column with 60 mL of ethyl ether/pentane
(1+1)(V/V), collecting the eluate in a second K-D flask equipped with a
10-mL concentrator tube. Add 15 mL of methanol to the K-D flask. This
fraction will contain N-nitrosodimethylamine, most of the N-nitrosodi-n-
propylamine and any diphenylamine that is present.
11.4.5 Concentrate both fractions as in Section 10.6, except use
pentane to prewet the column. When the apparatus is cool, remove the
Snyder column and rinse the flask and its lower joint into the
concentrator tube with 1 to 2 mL of pentane. Analyze the fractions by
gas chromatography (Section 12).
12. Gas Chromatography
12.1 N-nitrosodiphenylamine completely reacts to form diphenylamine
at the normal operating temperatures of a GC injection port (200 to 250
[deg]C). Thus, N-nitrosodiphenylamine is chromatographed and detected as
diphenylamine. Accurate determination depends on removal of
diphenylamine that may be present in the original extract prior to GC
analysis (See Section 11).
12.2 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Examples of the separations
achieved by Column 1 are shown in Figures 1 and 2. Other packed or
capillary (open-tubular) columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
12.3 Calibrate the system daily as described in Section 7.
[[Page 140]]
12.4 If the extract has not been subjected to one of the cleanup
procedures in Section 11, it is necessary to exchange the solvent from
methylene chloride to methanol before the thermionic detector can be
used. To a 1 to 10-mL volume of methylene chloride extract in a
concentrator tube, add 2 mL of methanol and a clean boiling chip. Attach
a two-ball micro-Snyder column to the concentrator tube. Prewet the
column by adding about 0.5 mL of methylene chloride to the top. Place
the micro-K-D apparatus on a boiling (100 [deg]C) water bath so that the
concentrator tube is partially immersed in the hot water. Adjust the
vertical position of the apparatus and the water temperature as required
to complete the concentration in 5 to 10 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood. When the apparent volume of liquid reaches
about 0.5 mL, remove the K-D apparatus and allow it to drain and cool
for at least 10 min. Remove the micro-Snyder column and rinse its lower
joint into the concentrator tube with 0.2 mL of methanol. Adjust the
final volume to 2.0 mL.
12.5 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatograph.
12.6 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \21\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, and
the resulting peak size in area or peak height units.
12.7 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.8 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.9 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.105
Equation 2
where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([micro]L).
Vt=Volume of total extract ([micro]L).
Vs=Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.106
Equation 3
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract
([micro]g).
Vo=Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \3\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \22\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 4 x MDL to 1000 x MDL. \22\
14.3 This method was tested by 17 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 0.8 to 55 [micro]g/L. \23\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
[[Page 141]]
References
1. Fine, D.H., Lieb, D., and Rufeh, R. ``Principle of Operation of
the Thermal Energy Analyzer for the Trace Analysis of Volatile and Non-
volatile N-nitroso Compounds,'' Journal of Chromatography, 107, 351
(1975).
2. Fine, D.H., Hoffman, F., Rounbehler, D.P., and Belcher, N.M.
``Analysis of N-nitroso Compounds by Combined High Performance Liquid
Chromatography and Thermal Energy Analysis,'' Walker, E.A., Bogovski, P.
and Griciute, L., Editors, N-nitroso Compounds--Analysis and Formation,
Lyon, International Agency for Research on Cancer (IARC Scientific
Publications No. 14), pp. 43-50 (1976).
3. 40 CFR part 136, appendix B.
4. ``Determination of Nitrosamines in Industrial and Municipal
Wastewaters,'' EPA 600/4-82-016, National Technical Information Service,
PB82-199621, Springfield, Virginia 22161, April 1982.
5. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
6. Buglass, A.J., Challis, B.C., and Osborn, M.R. ``Transnitrosation
and Decomposition of Nitrosamines,'' Bogovski, P. and Walker, E.A.,
Editors, N-nitroso Compounds in the Environment, Lyon, International
Agency for Research on Cancer (IARC Scientific Publication No. 9), pp.
94-100 (1974).
7. Burgess, E.M., and Lavanish, J.M. ``Photochemical Decomposition
of N-nitrosamines,'' Tetrahedon Letters, 1221 (1964)
8. Druckrey, H., Preussmann, R., Ivankovic, S., and Schmahl, D.
``Organotrope Carcinogene Wirkungen bei 65 Verschiedenen N-
NitrosoVerbindungen an BD-Ratten,'' Z. Krebsforsch., 69, 103 (1967).
9. Fiddler, W. ``The Occurrence and Determination of N-nitroso
Compounds,'' Toxicol. Appl. Pharmacol., 31, 352 (1975).
10. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
11. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
Part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
12. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
13. Lijinsky, W. ``How Nitrosamines Cause Cancer,'' New Scientist,
73, 216 (1977).
14. Mirvish, S.S. ``N-Nitroso compounds: Their Chemical and in vivo
Formation and Possible Importance as Environmental Carcinogens,'' J.
Toxicol. Environ. Health, 3, 1267 (1977).
15. ``Reconnaissance of Environmental Levels of Nitrosamines in the
Central United States,'' EPA-330/1-77-001, National Enforcement
Investigations Center, U.S. Environmental Protection Agency (1977).
16. ``Atmospheric Nitrosamine Assessment Report,'' Office of Air
Quality Planning and Standards, U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina (1976).
17. ``Scientific and Technical Assessment Report on Nitrosamines,''
EPA-660/6-7-001, Office of Research and Development, U.S. Environmental
Protection Agency (1976).
18. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value of 1.22
derived in this report.)
19. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
20. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
21. Burke, J. A. ``Gas Chromatography for Pesticide Residue
Analysis; Some Practical Aspects,'' Journal of the Association of
Official Analytical Chemists, 48, 1037 (1965).
22. ``Method Detection Limit and Analytical Curve Studies EPA
Methods 606, 607, and 608,'' Special letter report for EPA Contract 68-
03-2606, U.S. Environmental Protection Agency, Environmental Monitoring
and Support Laboratory, Cincinnati, Ohio 45268, June 1980.
23. ``EPA Method Study 17 Method 607--Nitrosamines,'' EPA 600/4-84-
051, National Technical Information Service, PB84-207646, Springfield,
Virginia 22161, June 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
-------------------------- detection
Parameter limit
Column 1 Column 2 ([micro]g/
L)
------------------------------------------------------------------------
N-Nitrosodimethylamine........... 4.1 0.88 0.15
N-Nitrosodi-n-propylamine........ 12.1 4.2 .46
[[Page 142]]
N-Nitrosodiphenylamine \a\....... \b\ 12.8 \c\ 6.4 .81
------------------------------------------------------------------------
Column 1 conditions: Chromosorb W-AW (80/100 mesh) coated with 10%
Carbowax 20 M/2% KOH packed in a 1.8 m long x 4mm ID glass column with
helium carrier gas at 40 mL/min flow rate. Column temperature held
isothermal at 110 [deg]C, except where otherwise indicated.
Column 2 conditions: Supelcoport (100/120 mesh) coated with 10% SP-2250
packed in a 1.8 m long x 4 mm ID glass column with helium carrier gas
at 40 mL/min flow rate. Column temperature held isothermal at 120
[deg]C, except where otherwise indicated.
\a\ Measured as diphenylamine.
\b\ 220 [deg]C column temperature.
\c\ 210 [deg]C column temperature.
Table 2--QC Acceptance Criteria--Method 607
----------------------------------------------------------------------------------------------------------------
Range for X
Test conc. Limit for s ([micro]g/ Range for
Parameter ([micro]g/ ([micro]g/ L) P, Ps
L) L) (percent)
----------------------------------------------------------------------------------------------------------------
N-Nitrosodimethylamine...................................... 20 3.4 4.6-20.0 13-109
N-Nitrosodiphenyl........................................... 20 6.1 2.1-24.5 D-139
N-Nitrosodi-n-propylamine................................... 20 5.7 11.5-26.8 45-146
----------------------------------------------------------------------------------------------------------------
s=Standard deviation for four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 607
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
N-Nitrosodimethylamine.......................................... 0.37C+0.06 0.25X-0.04 0.25X+0.11
N-Nitrosodiphenylamine.......................................... 0.64C+0.52 0.36X-1.53 0.46X-0.47
N-Nitrosodi-n-propylamine....................................... 0.96C-0.07 0.15X+0.13 0.21X+0.15
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 143]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.017
[[Page 144]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.018
[[Page 145]]
Method 608--Organochlorine Pesticides and PCBs
1. Scope and Application
1.1 This method covers the determination of certain organochlorine
pesticides and PCBs. The following parameters can be determined by this
method:
------------------------------------------------------------------------
Parameter STORET No. CAS No.
------------------------------------------------------------------------
Aldrin...................................... 39330 309-00-2
[alpha]-BHC................................. 39337 319-84-6
[beta]-BHC.................................. 39338 319-85-7
[delta]-BHC................................. 34259 319-86-8
[gamma]-BHC................................. 39340 58-89-9
Chlordane................................... 39350 57-74-9
4,4'-DDD.................................... 39310 72-54-8
4,4'-DDE.................................... 39320 72-55-9
4,4'-DDT.................................... 39300 50-29-3
Dieldrin.................................... 39380 60-57-1
Endosulfan I................................ 34361 959-98-8
Endosulfan II............................... 34356 33212-65-9
Endosulfan sulfate.......................... 34351 1031-07-8
Eldrin...................................... 39390 72-20-8
Endrin aldehyde............................. 34366 7421-93-4
Heptachlor.................................. 39410 76-44-8
Heptachlor epoxide.......................... 39420 1024-57-3
Toxaphene................................... 39400 8001-35-2
PCB-1016.................................... 34671 12674-11-2
PCB-1221.................................... 39488 1104-28-2
PCB-1232.................................... 39492 11141-16-5
PCB-1242.................................... 39496 53469-21-9
PCB-1248.................................... 39500 12672-29-6
PCB-1254.................................... 39504 11097-69-1
PCB-1260.................................... 39508 11096-82-5
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of the compounds listed above in municipal and industrial
discharges as provided under 40 CFR 136.1. When this method is used to
analyze unfamiliar samples for any or all of the compounds above,
compound identifications should be supported by at least one additional
qualitative technique. This method describes analytical conditions for a
second gas chromatographic column that can be used to confirm
measurements made with the primary column. Method 625 provides gas
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the
qualitative and quantitative confirmation of results for all of the
parameters listed above, using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 The sample extraction and concentration steps in this method are
essentially the same as in Methods 606, 609, 611, and 612. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. The analyst is
allowed the latitude, under Section 12, to select chromatographic
conditions appropriate for the simultaneous measurement of combinations
of these parameters.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and exchanged to hexane during concentration
to a volume of 10 mL or less. The extract is separated by gas
chromatography and the parameters are then measured with an electron
capture detector. \2\
2.2 The method provides a Florisil column cleanup procedure and an
elemental sulfur removal procedure to aid in the elimination of
interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
[[Page 146]]
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Interferences by phthalate esters can pose a major problem in
pesticide analysis when using the electron capture detector. These
compounds generally appear in the chromatogram as large late eluting
peaks, especially in the 15 and 50% fractions from Florisil. Common
flexible plastics contain varying amounts of phthalates. These
phthalates are easily extracted or leached from such materials during
laboratory operations. Cross contamination of clean glassware routinely
occurs when plastics are handled during extraction steps, especially
when solvent-wetted surfaces are handled. Interferences from phthalates
can best be minimized by avoiding the use of plastics in the laboratory.
Exhaustive cleanup of reagents and glassware may be required to
eliminate background phthalate contamination. \4,5\ The interferences
from phthalate esters can be avoided by using a microcoulometric or
electrolytic conductivity detector.
3.3 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedures in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified
6-8 for the information of the analyst.
4.2 The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: 4,4'-DDT, 4,4'-DDD, the BHCs, and the PCBs. Primary
standards of these toxic compounds should be prepared in a hood. A
NIOSH/MESA approved toxic gas respirator should be worn when the analyst
handles high concentrations of these toxic compounds.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during composting. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2. Glassware (All specifications are suggested. Catalog numbers
are included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Chromatographic column--400 mm long x 22 mm ID, with Teflon
stopcock and coarse frit filter disc (Kontes K-42054 or equivalent).
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna/Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with gas
chromatograph suitable for on-column injection and all required
accessories including syringes, analytical columns, gases, detector, and
strip-
[[Page 147]]
chart recorder. A data system is recommended for measuring peak areas.
5.6.1 Column 1--1.8 m long x 4 mm ID glass, packed with 1.5% SP-
2250/1.95% SP-2401 on Supelcoport (100/120 mesh) or equivalent. This
column was used to develop the method performance statements in Section
14. Guidelines for the use of alternate column packings are provided in
Section 12.1.
5.6.2 Column 2--1.8 m long x 4 mm ID glass, packed with 3% OV-1 on
Supelcoport (100/120 mesh) or equivalent.
5.6.3 Detector--Electron capture detector. This detector has proven
effective in the analysis of wastewaters for the parameters listed in
the scope (Section 1.1), and was used to develop the method performance
statements in Section 14. Guidelines for the use of alternate detectors
are provided in Section 12.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.3 Sodium thiosulfate--(ACS) Granular.
6.4 Sulfuric acid (1+1)--Slowly, add 50 mL to
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.5 Acetone, hexane, isooctane, methylene chloride--Pesticide
quality or equivalent.
6.6 Ethyl ether--Nanograde, redistilled in glass if necessary.
6.6.1 Ethyl ether must be shown to be free of peroxides before it is
used as indicated by EM Laboratories Quant test strips. (Available from
Scientific Products Co., Cat. No. P1126-8, and other suppliers.)
6.6.2 Procedures recommended for removal of peroxides are provided
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative
must be added to each liter of ether.
6.7 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.8 Florisil--PR grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in the dark in glass containers with ground glass
stoppers or foil-lined screw caps. Before use, activate each batch at
least 16 h at 130 [deg]C in a foil-covered glass container and allow to
cool.
6.9 Mercury--Triple distilled.
6.10 Copper powder--Activated.
6.11 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.11.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in isooctane and dilute
to volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.11.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.11.3 Stock standard solutions must be replaced after six months,
or sooner if comparison with check standards indicates a problem.
6.12 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatographic operating conditions equivalent to
those given in Table 1. The gas chromatographic system can be calibrated
using the external standard technique (Section 7.2) or the internal
standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with isooctane. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can
[[Page 148]]
be suggested that is applicable to all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with isooctane. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.107
Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, the test must
be repeated using a fresh calibration standard. Alternatively, a new
calibration curve must be prepared for that compound.
7.5 The cleanup procedure in Section 11 utilizes Florisil column
chromatography. Florisil from different batches or sources may vary in
adsorptive capacity. To standardize the amount of Florisil which is
used, the use of lauric acid value \9\ is suggested. The referenced
procedure determines the adsorption from hexane solution of lauric acid
(mg) per g of Florisil. The amount of Florisil to be used for each
column is calculated by dividing 110 by this ratio and multiplying by 20
g.
7.6 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
[[Page 149]]
8.2.1 A quality control (QC) check sample concentrate is required
containing each single-component parameter of interest at the following
concentrations in acetone: 4,4'-DDD, 10 [micro]g/mL; 4,4'-DDT, 10
[micro]g/mL; endosulfan II, 10 [micro]g/mL; endosulfan sulfate, 10
[micro]g/mL; endrin, 10 [micro]g/mL; any other single-component
pesticide, 2 [micro]g/mL. If this method is only to be used to analyze
for PCBs, chlordane, or toxaphene, the QC check sample concentrate
should contain the most representative multicomponent parameter at a
concentration of 50 [micro]g/mL in acetone. The QC check sample
concentrate must be obtained from the U.S. Environmental Protection
Agency, Environmental Monitoring and Support Laboratory in Cincinnati,
Ohio, if available. If not available from that source, the QC check
sample concentrate must be obtained from another external source. If not
available from either source above, the QC check sample concentrate must
be prepared by the laboratory using stock standards prepared
independently from those used for calibration.
8.2.2 Using a pipet, prepare QC check samples at the test
concentrations shown in Table 3 by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/mL; and the
standard deviation of the recovery (s) in [micro]g/mL, for each
parameter using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 3. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Table 3 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.2.
8.2.6.2 Beginning with Section 8.2.2, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compmunds of interest beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at the test concentration in Section 8.2.2 or 1 to 5
times higher than the background concentration determined in Section
8.3.2, whichever concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or the test concentration in Section 8.2.2.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 3. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\10\ If spiking was performed at a concentration lower than the test
concentration in Section 8.2.2, the analyst must use either the QC
acceptance criteria in Table 3, or optional QC acceptance criteria
calculated for the specific spike concentration. To calculate optional
acceptance criteria for the recovery of a parameter: (1) Calculate
accuracy (X') using the equation in Table 4, substituting the spike
concentration (T) for C; (2) calculate overall precision (S') using the
equation in Table 4, substituting X'
[[Page 150]]
for X; (3) calculate the range for recovery at the spike concentration
as (100 X'/T)2.44(100 S'/T)%. \10\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory. If the entire list of parameters in Table 3 must be measured
in the sample in Section 8.3, the probability that the analysis of a QC
check standard will be required is high. In this case the QC check
standard should be routinely analyzed with the spike sample.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standards to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
3. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2 sp to P+2 sp.
If P=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \11\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction. If the samples will not be
extracted within 72 h of collection, the sample should be adjusted to a
pH range of 5.0 to 9.0 with sodium hydroxide solution or sulfuric acid.
Record the volume of acid or base used. If aldrin is to be determined,
add sodium thiosulfate when residual chlorine is present. EPA Methods
330.4 and 330.5 may be used for measurement of residual chlorine. \12\
Field test kits are available for this purpose.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optium technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
[[Page 151]]
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.7 Increase the temperature of the hot water bath to about 80
[deg]C. Momeltarily remove the Snyder column, add 50 mL of hexane and a
new boiling chip, and reattach the Snyder column. Concentrate the
extract as in Section 10.6, except use hexane to prewet the column. The
elapsed time of concentration should be 5 to 10 min.
10.8 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL
syringe is recommended for this operation. Stopper the concentrator tube
and store refrigerated if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial. If the sample
extract requires no further cleanup, proceed with gas chromatographic
analysis (Section 12). If the sample requires further cleanup, proceed
to Section 11.
10.9 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use either procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the method as revised
to incorporate the cleanup procedure. The Florisil column allows for a
select fractionation of the compounds and will eliminate polar
interferences. Elemental sulfur, which interferes with the electron
capture gas chromatography of certain pesticides, can be removed by the
technique described in Section 11.3.
11.2 Florisil column cleanup:
11.2.1 Place a weight of Florisil (nominally 20 g) predetermined by
calibration (Section 7.5), into a chromatographic column. Tap the column
to settle the Florisil and add 1 to 2 cm of anhydrous sodium sulfate to
the top.
11.2.2 Add 60 mL of hexane to wet and rinse the sodium sulfate and
Florisil. Just prior to exposure of the sodium sulfate layer to the air,
stop the elution of the hexane by closing the stopcock on the
chromatographic column. Discard the eluate.
11.2.3 Adjust the sample extract volume to 10 mL with hexane and
transfer it from the K-D concentrator tube onto the column. Rinse the
tube twice with 1 to 2 mL of hexane, adding each rinse to the column.
11.2.4 Place a 500-mL K-D flask and clean concentrator tube under
the chromatographic column. Drain the column into the flask until the
sodium sulfate layer is nearly exposed. Elute the column with 200 mL of
6% ethyl ether in hexane (V/V) (Fraction 1) at a rate of about 5 mL/min.
Remove the K-D flask and set it aside for later concentration. Elute the
column again, using 200 mL of 15% ethyl ether in hexane (V/V) (Fraction
2), into a second K-D flask. Perform the third elution using 200 mL of
50% ethyl ether in hexane (V/V) (Fraction 3). The elution patterns for
the pesticides and PCBs are shown in Table 2.
11.2.5 Concentrate the fractions as in Section 10.6, except use
hexane to prewet the column and set the water bath at about 85 [deg]C.
When the apparatus is cool, remove the Snyder column and rinse the flask
and its lower joint into the concentrator tube with hexane. Adjust the
volume of each fraction to 10 mL with hexane and analyze by gas
chromatography (Section 12).
11.3 Elemental sulfur will usually elute entirely in Fraction 1 of
the Florisil column cleanup. To remove sulfur interference from this
fraction or the original extract, pipet 1.00 mL of the concentrated
extract into a clean concentrator tube or Teflon-sealed vial. Add one to
three drops of mercury and seal. \13\ Agitate the contents of the vial
for 15 to 30 s. Prolonged shaking (2 h) may be required. If so, this may
be accomplished with a reciprocal shaker. Alternatively, activated
[[Page 152]]
copper powder may be used for sulfur removal. \14\ Analyze by gas
chromatography.
12. Gas Chromatography
12.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Examples of the separations
achieved by Column 1 are shown in Figures 1 to 10. Other packed or
capillary (open-tubular) columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
12.2 Calibrate the system daily as described in Section 7.
12.3 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatograph.
12.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \15\ Smaller
(1.0 uL) volumes may be injected if automatic devices are employed.
Record the volume injected to the nearest 0.05 [micro]L, the total
extract volume, and the resulting peak size in area or peak height
units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.108
Equation 2
where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([micro]L).
Vt=Volume of total extract ([micro]L).
Vs=Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.109
Equation 3
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract
([micro]g).
Vo=Volume of water extracted (L).
13.2 When it is apparent that two or more PCB (Aroclor) mixtures are
present, the Webb and McCall procedure \16\ may be used to identify and
quantify the Aroclors.
13.3 For multicomponent mixtures (chlordane, toxaphene, and PCBs)
match retention times of peaks in the standards with peaks in the
sample. Quantitate every identifiable peak unless interference with
individual peaks persist after cleanup. Add peak height or peak area of
each identified peak in the chromatogram. Calculate as total response in
the sample versus total response in the standard.
13.4 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \17\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 4xMDL to 1000xMDL with the following
exceptions: Chlordane recovery at 4xMDL was low (60%); Toxaphene
recovery was demonstrated linear over the range of 10xMDL to 1000xMDL.
\17\
14.3 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial
[[Page 153]]
wastewaters spiked at six concentrations. \18\ Concentrations used in
the study ranged from 0.5 to 30 [micro]g/L for single-component
pesticides and from 8.5 to 400 [micro]g/L for multicomponent parameters.
Single operator precision, overall precision, and method accuracy were
found to be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 4.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Pesticides and PCBs in Industrial and
Municipal Wastewaters,'' EPA 600/4-82-023, National Technical
Information Service, PB82-214222, Springfield, Virginia 22161, April
1982.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
4. Giam, C.S., Chan, H.S., and Nef, G.S., ``Sensitive Method for
Determination of Phthalate Ester Plasticizers in Open-Ocean Biota
Samples,'' Analytical Chemistry, 47, 2225 (1975).
5. Giam, C.S., Chan, H.S. ``Control of Blanks in the Analysis of
Phthalates in Air and Ocean Biota Samples,'' U.S. National Bureau of
Standards, Special Publication 442, pp. 701-708, 1976.
6. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
7. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
8. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
9. Mills, P.A. ``Variation of Florisil Activity: Simple Method for
Measuring Absorbent Capacity and Its Use in Standardizing Florisil
Columns,'' Journal of the Association of Official Analytical Chemists,
51, 29, (1968).
10. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
11. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
12. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
13. Goerlitz, D.F., and Law, L.M. Bulletin for Environmental
Contamination and Toxicology, 6, 9 (1971).
14. ``Manual of Analytical Methods for the Analysis of Pesticides in
Human and Environmental Samples,'' EPA-600/8-80-038, U.S. Environmental
Protection Agency, Health Effects Research Laboratory, Research Triangle
Park, North Carolina.
15. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
16. Webb, R.G., and McCall, A.C. ``Quantitative PCB Standards for
Election Capture Gas Chromatography,'' Journal of Chromatographic
Science, 11, 366 (1973).
17. ``Method Detection Limit and Analytical Curve Studies, EPA
Methods 606, 607, and 608,'' Special letter report for EPA Contract 68-
03-2606, U.S. Environmental Protection Agency, Environmental Monitoring
and Support Laboratory, Cincinnati, Ohio 45268, June 1980.
18. ``EPA Method Study 18 Method 608--Organochlorine Pesticides and
PCBs,'' EPA 600/4-84-061, National Technical Information Service, PB84-
211358, Springfield, Virginia 22161, June 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
-------------------------- detection
Parameter limit
Col. 1 Col. 2 ([micro]g/L)
------------------------------------------------------------------------
[alpha]-BHC.................... 1.35 1.82 0.003
[gamma]-BHC.................... 1.70 2.13 0.004
[beta]-BHC..................... 1.90 1.97 0.006
Heptachlor..................... 2.00 3.35 0.003
[delta]-BHC.................... 2.15 2.20 0.009
Aldrin......................... 2.40 4.10 0.004
Heptachlor epoxide............. 3.50 5.00 0.083
Endosulfan I................... 4.50 6.20 0.014
4,4'-DDE....................... 5.13 7.15 0.004
Dieldrin....................... 5.45 7.23 0.002
Endrin......................... 6.55 8.10 0.006
[[Page 154]]
4,4'-DDD....................... 7.83 9.08 0.011
Endosulfan II.................. 8.00 8.28 0.004
4,4'-DDT....................... 9.40 11.75 0.012
Endrin aldehyde................ 11.82 9.30 0.023
Endosulfan sulfate............. 14.22 10.70 0.066
Chlordane...................... mr mr 0.014
Toxaphene...................... mr mr 0.24
PCB-1016....................... mr mr nd
PCB-1221....................... mr mr nd
PCB-1232....................... mt mr nd
PCB-1242....................... mr mr 0.065
PCB-1248....................... mr mr nd
PCB-1254....................... mr mr nd
PCB-1260....................... mr mr nd
------------------------------------------------------------------------
AColumn 1 conditions: Supelcoport (100/120 mesh) coated with 1.5% SP-
2250/1.95% SP-2401 packed in a 1.8 m long x 4 mm ID glass column with
5% methane/95% argon carrier gas at 60 mL/min flow rate. Column
temperature held isothermal at 200 [deg]C, except for PCB-1016 through
PCB-1248, should be measured at 160 [deg]C.
AColumn 2 conditions: Supelcoport (100/120 mesh) coated with 3% OV-1
packed in a 1.8 m long x 4 mm ID glass column with 5% methane/95%
argon carrier gas at 60 mL/min flow rate. Column temperature held
isothermal at 200 [deg]C for the pesticides; at 140 [deg]C for PCB-
1221 and 1232; and at 170 [deg]C for PCB-1016 and 1242 to 1268.
Amr=Multiple peak response. See Figures 2 thru 10.
And=Not determined.
Table 2--Distribution of Chlorinated Pesticides and PCBs into Florisil
Column Fractions 2
------------------------------------------------------------------------
Percent recovery by fraction \a\
Parameter --------------------------------------
1 2 3
------------------------------------------------------------------------
Aldrin........................... 100 ........... ...........
[alpha]-BHC...................... 100 ........... ...........
[beta]-BHC....................... 97 ........... ...........
[delta]-BHC...................... 98 ........... ...........
[gamma]-BHC...................... 100 ........... ...........
Chlordane........................ 100 ........... ...........
4,4'-DDD......................... 99 ........... ...........
4,4'-DDE......................... 98 ........... ...........
4,4'-DDT......................... 100 ........... ...........
Dieldrin......................... 0 100 ...........
Endosulfan I..................... 37 64 ...........
Endosulfan II.................... 0 7 91
Endosulfan sulfate............... 0 0 106
Endrin........................... 4 96 ...........
Endrin aldehyde.................. 0 68 26
Heptachlor....................... 100 ........... ...........
Heptachlor epoxide............... 100 ........... ...........
Toxaphene........................ 96 ........... ...........
PCB-1016......................... 97 ........... ...........
PCB-1221......................... 97 ........... ...........
PCB-1232......................... 95 4 ...........
PCB-1242......................... 97 ........... ...........
PCB-1248......................... 103 ........... ...........
PCB-1254......................... 90 ........... ...........
PCB-1260......................... 95 ........... ...........
------------------------------------------------------------------------
\a\ Eluant composition:
Fraction 1-6% ethyl ether in hexane.
Fraction 2-15% ethyl ether in hexane.
Fraction 3-50% ethyl ether in hexane.
Table 3--QC Acceptance Criteria--Method 608
----------------------------------------------------------------------------------------------------------------
Range for
Test conc. Limit for s X Range for
Parameter ([micro]g/ ([micro]g/L) ([micro]g/ P, Ps(%)
L) L)
----------------------------------------------------------------------------------------------------------------
Aldrin...................................................... 2.0 0.42 1.08-2.24 42-122
[alpha]-BHC................................................. 2.0 0.48 0.98-2.44 37-134
[beta]-BHC.................................................. 2.0 0.64 0.78-2.60 17-147
[delta]-BHC................................................. 2.0 0.72 1.01-2.37 19-140
[gamma]-BHC................................................. 2.0 0.46 0.86-2.32 32-127
[[Page 155]]
Chlordane................................................... 50 10.0 27.6-54.3 45-119
4,4 '-DDD................................................... 10 2.8 4.8-12.6 31-141
4,4 '-DDE................................................... 2.0 0.55 1.08-2.60 30-145
4,4'-DDT.................................................... 10 3.6 4.6-13.7 25-160
Dieldrin.................................................... 2.0 0.76 1.15-2.49 36-146
Endosulfan I................................................ 2.0 0.49 1.14-2.82 45-153
Endosulfan II............................................... 10 6.1 2.2-17.1 D-202
Endosulfan Sulfate.......................................... 10 2.7 3.8-13.2 26-144
Endrin...................................................... 10 3.7 5.1-12.6 30-147
Heptachlor.................................................. 2.0 0.40 0.86-2.00 34-111
Heptachlor epoxide.......................................... 2.0 0.41 1.13-2.63 37-142
Toxaphene................................................... 50.0 12.7 27.8-55.6 41-126
PCB-1016.................................................... 50 10.0 30.5-51.5 50-114
PCB-1221.................................................... 50 24.4 22.1-75.2 15-178
PCB-1232.................................................... 50 17.9 14.0-98.5 10-215
PCB-1242.................................................... 50 12.2 24.8-69.6 39-150
PCB-1248.................................................... 50 15.9 29.0-70.2 38-158
PCB-1254.................................................... 50 13.8 22.2-57.9 29-131
PCB-1260.................................................... 50 10.4 18.7-54.9 8-127
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 4. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 4.
Table 4--Method Accuracy and Precision as Functions of Concentration--Method 608
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst
Parameter recovery, X' precision, sr' Overall precision,
([micro]g/L) ([micro]g/L) S' ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Aldrin.............................................. 0.81C+0.04 0.16X-0.04 0.20X-0.01
[alpha]-BHC......................................... 0.84C+0.03 0.13X+0.04 0.23X-0.00
[beta]-BHC.......................................... 0.81C+0.07 0.22X-0.02 0.33X-0.05
[delta]-BHC......................................... 0.81C+0.07 0.18X+0.09 0.25X+0.03
[gamma]-BHC......................................... 0.82C-0.05 0.12X+0.06 0.22X+0.04
Chlordane........................................... 0.82C-0.04 0.13X+0.13 0.18X+0.18
4,4'-DDD............................................ 0.84C+0.30 0.20X-0.18 0.27X-0.14
4,4'-DDE............................................ 0.85C+0.14 0.13X+0.06 0.28X-0.09
4,4'-DDT............................................ 0.93C-0.13 0.17X+0.39 0.31X-0.21
Dieldrin............................................ 0.90C+0.02 0.12X+0.19 0.16X+0.16
Endosulfan I........................................ 0.97C+0.04 0.10X+0.07 0.18X+0.08
Endosulfan II....................................... 0.93C+0.34 0.41X--0.65 0.47X-0.20
Endosulfan Sulfate.................................. 0.89C-0.37 0.13X+0.33 0.24X+0.35
Endrin.............................................. 0.89C-0.04 0.20X+0.25 0.24X+0.25
Heptachlor.......................................... 0.69C+0.04 0.06X+0.13 0.16X+0.08
Heptachlor epoxide.................................. 0.89C+0.10 0.18X-0.11 0.25X-0.08
Toxaphene........................................... 0.80C+1.74 0.09X+3.20 0.20X+0.22
PCB-1016............................................ 0.81C+0.50 0.13X+0.15 0.15X+0.45
PCB-1221............................................ 0.96C+0.65 0.29X-0.76 0.35X-0.62
PCB-1232............................................ 0.91C+10.79 0.21X-1.93 0.31X+3.50
PCB-1242............................................ 0.93C+0.70 0.11X+1.40 0.21X+1.52
PCB-1248............................................ 0.97C+1.06 0.17X+0.41 0.25X-0.37
PCB-1254............................................ 0.76C+2.07 0.15X+1.66 0.17X+3.62
PCB-1260............................................ 0.66C+3.76 0.22X-2.37 0.39X-4.86
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 156]]
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Method 609--Nitroaromatics and Isophorone
1. Scope and Application
1.1 This method covers the determination of certain nitroaromatics
and isophorone. The following parameters may be determined by this
method:
------------------------------------------------------------------------
Parameter STORET No. CAS No.
------------------------------------------------------------------------
2,4-Dinitrotoluene............................ 34611 121-14-2
2,6-Dinitrotoluene............................ 34626 606-20-2
Isophorone.................................... 34408 78-59-1
Nitrobenzene.................................. 34447 98-95-3
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of
[[Page 166]]
the compounds listed above in municipal and industrial discharges as
provided under 40 CFR 136.1. When this method is used to analyze
unfamiliar samples for any or all of the compounds above, compound
identifications should be supported by at least one additional
qualitative technique. This method describes analytical conditions for a
second gas chromatographic column that can be used to confirm
measurements made with the primary column. Method 625 provides gas
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the
qualitative and quantitative confirmation of results for all of the
parameters listed above, using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 The sample extraction and concentration steps in this method are
essentially the same as in Methods 606, 608, 611, and 612. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. The analyst is
allowed the latitude, under Section 12, to select chromatographic
conditions appropriate for the simultaneous measurement of combinations
of these parameters.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and exchanged to hexane during concentration
to a volume of 10 mL or less. Isophorone and nitrobenzene are measured
by flame ionization detector gas chromatography (FIDGC). The
dinitrotoluenes are measured by electron capture detector gas
chromatography (ECDGC). \2\
2.2 The method provides a Florisil column cleanup procedure to aid
in the elimination of interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baseliles in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedure in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified
4-6 for the information of the analyst.
[[Page 167]]
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Chromatographic column--100 mm long x 10 mm ID, with Teflon
stopcock.
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.8 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with gas
chromatograph suitable for on-column injection and all required
accessories including syringes, analytical columns, gases, detector, and
strip-chart recorder. A data system is recommended for measuring peak
areas.
5.6.1 Column 1--1.2 m long x 2 or 4 mm ID glass, packed with 1.95%
QF-1/1.5% OV-17 on Gas-Chrom Q (80/100 mesh) or equivalent. This column
was used to develop the method performance statements given in Section
14. Guidelines for the use of alternate column packings are provided in
Section 12.1.
5.6.2 Column 2--3.0 m long x 2 or 4 mm ID glass, packed with 3% OV-
101 on Gas-Chrom Q (80/100 mesh) or equivalent.
5.6.3 Detectors--Flame ionization and electron capture detectors.
The flame ionization detector (FID) is used when determining isophorone
and nitrobenzene. The electron capture detector (ECD) is used when
determining the dinitrotoluenes. Both detectors have proven effective in
the analysis of wastewaters and were used in develop the method
performance statements in Section 14. Guidelines for the use to
alternate detectors are provided in Section 12.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.3 Sulfuric acid (1+1)--Slowly, add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.4 Acetone, hexane, methanol, methylene chloride--Pesticide quality
or equivalent.
6.5 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.6 Florisil--PR grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in dark in glass containers with ground glass stoppers
or foil-lined screw caps. Before use, activate each batch at least 16 h
at 200 [deg]C in a foil-covered glass container and allow to cool.
6.7 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.7.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in hexane and dilute to
volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.7.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles.
[[Page 168]]
Store at 4 [deg]C and protect from light. Stock standard solutions
should be checked frequently for signs of degradation or evaporation,
especially just prior to preparing calibration standards from them.
6.7.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with check standards indicates a problem.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatographic operating conditions equivalent to
those given in Table 1. The gas chromatographic system can be calibrated
using the external standard technique (Section 7.2) or the internal
standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with hexane. One of the external standards should be at a concentration
near, but above, the MDL (Table 1) and the other concentrations should
correspond to the expected range of concentrations found in real samples
or should define the working range of the detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD) linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flash. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with hexane. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.110
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the
RF can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to
[[Page 169]]
generate acceptable accuracy and precision with this method. This
ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1,5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest in acetone at a concentration of
20 [micro]g/mL for each dinitrotoluene and 100 [micro]g/mL for
isophorone and nitrobenzene. The QC check sample concentrate must be
obtained from the U.S. Environmental Protection Agency, Environmental
Monitoring and Support Laboratory in Cincinnati, Ohio, if available. If
not available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Using a pipet, prepare QC check samples at the test
concentrations shown in Table 2 by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter. Locate and correct the
source of the problem and repeat the test for all parameters of interest
beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at the test concentration in Section 8.2.2 or 1 to 5
times higher than the background concentration determined in Section
8.3.2, whichever concentration would be larger.
8.3.1.3 If it is impractical to determile background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or the test concentration in Section 8.2.2.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100 (A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement
[[Page 170]]
of both the background and spike concentrations, assuming a spike to
background ratio of 5:1. This error will be accounted for to the extent
that the analyst's spike to background ratio approaches 5:1. \7\ If
spiking was performed at a concentration lower than the test
concentration in Section 8.2.2, the analyst must use either the QC
acceptance criteria in Table 2, or optional QC acceptance criteria
calculated for the specific spike concentration. To calculate optional
acceptance criteria for the recovery of a parameter: (1) Calculate
accuracy (X') using the equation in Table 3, substituting the spike
concentration (T) for C; (2) calculate overall precision (S') using the
equation in Table 3, substituting X' for X8; (3) calculate the range for
recovery at the spike concentration as (100 X'/T) 2.44 (100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4. If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of QC program for the laboratory, method accuracy for
wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If P=90% and sp = 10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \8\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel. Check the pH of the sample with wide-range pH paper
and adjust to within the range of 5 to 9 with sodium hydroxide solution
or sulfuric acid.
10.2 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration
[[Page 171]]
of the emulsion through glass wool, centrifugation, or other physical
methods. Collect the methylene chloride extract in a 250-mL Erlenmeyer
flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Sections 10.7 and 10.8 describe a procedure for exchanging the
methylene chloride solvent to hexane while concentrating the extract
volume to 1.0 mL. When it is not necessary to achieve the MDL in Table
2, the solvent exchange may be made by the addition of 50 mL of hexane
and concentration to 10 mL as described in Method 606, Sections 10.7 and
10.8.
10.7 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.8 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of methylene chloride. A
5-mL syringe is recommended for this operation. Add 1 to 2 mL of hexane
and a clean boiling chip to the concentrator tube and attach a two-ball
micro-Snyder column. Prewet the column by adding about 0.5 mL of hexane
to the top. Place the micro-K-D apparatus on a hot water bath (60 to 65
[deg]C) so that the concentrator tube is partially immersed in the hot
water. Adjust the vertical position of the apparatus and the water
temperature as required to complete the concentration in 5 to 10 min. At
the proper rate of distillation the balls of the column will actively
chatter but the chambers will not flood. When the apparent volume of
liquid reaches 0.5 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.9 Remove the micro-Snyder column and rinse its lower joint into
the concentrator tube with a minimum amount of hexane. Adjust the
extract volume to 1.0 mL. Stopper the concentrator tube and store
refrigerated if further processing will not be performed immediately. If
the extract will be stored longer than two days, it should be
transferred to a Teflon-sealed screw-cap vial. If the sample extract
requires no further cleanup, proceed with gas chromatographic analysis
(Section 12). If the sample requires further cleanup, proceed to Section
11.
10.10 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use the procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the method as revised
to incorporate the cleanup procedure.
11.2 Florisil column cleanup:
11.2.1 Prepare a slurry of 10 g of activated Florisil in methylene
chloride/hexane (1+9)(V/V) and place the Florisil into a chromatographic
column. Tap the column to settle the Florisil and add 1 cm of anhydrous
sodium sulfate to the top. Adjust the elution rate to about 2 mL/min.
11.2.2 Just prior to exposure of the sodium sulfate layer to the
air, quantitatively transfer the sample extract onto the column using an
additional 2 mL of hexane to complete the transfer. Just prior to
exposure of the sodium sulfate layer to the air, add 30 mL of methylene
chloride/hexane (1 + 9)(V/V) and continue the elution of the column.
Discard the eluate.
11.2.3 Next, elute the column with 30 mL of acetone/methylene
chloride (1 + 9)(V/V) into a 500-mL K-D flask equipped with a 10-mL
concentrator tube. Concentrate the collected fraction as in Sections
10.6, 10.7, 10.8, and 10.9 including the solvent exchange to 1 mL of
hexane. This fraction should contain the nitroaromatics and isophorone.
Analyze by gas chromatography (Section 12).
12. Gas Chromatography
12.1 Isophorone and nitrobenzene are analyzed by injection of a
portion of the extract into an FIDGC. The dinitrotoluenes are analyzed
by a separate injection into an ECDGC. Table 1 summarizes the
recommended operating conditions for the gas chromatograph.
[[Page 172]]
Included in this table are retention times and MDL that can be achieved
under these conditions. Examples of the separations achieved by Column 1
are shown in Figures 1 and 2. Other packed or capillary (open-tubular)
columns, chromatographic conditions, or detectors may be used if the
requirements of Section 8.2 are met.
12.2 Calibrate the system daily as described in Section 7.
12.3 If the internal standard calibration procedure is being used,
the internal standard must be added to the same extract and mixed
thoroughly immediately before injection into the gas chromatograph.
12.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \9\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, the
total extract volume, and the resulting peak size in area or peak height
units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.111
Equation 2
where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([micro]L).
Vt=Volume of total extract ([micro]L).
Vs=Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.112
Equation 3
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract
([micro]g).
Vo=Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \10\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 7xMDL to 1000xMDL. \10\
14.3 This method was tested by 18 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 1.0 to 515 [micro]g/L. \11\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Nitroaromatic Compounds and Isophorone in
Industrial and Municipal Wastewaters,'' EPA 600/ 4-82-024, National
Technical Information Service, PB82-208398, Springfield, Virginia 22161,
May 1982.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
[[Page 173]]
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
9. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
10. ``Determination of Method Detection Limit and Analytical Curve
for EPA Method 609--Nitroaromatics and Isophorone,'' Special letter
report for EPA Contract 68-03-2624, U.S. Environmental Protection
Agency, Environmental Monitoring and Support Laboratory, Cincinnati,
Ohio 45268, June 1980.
11. ``EPA Method Study 19, Method 609 (Nitroaromatics and
Isophorone),'' EPA 600/4-84-018, National Technical Information Service,
PB84-176908, Springfield, Virginia 22161, March 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
----------------------------------------------------------------------------------------------------------------
Retention time (min) Method detection limit
---------------------------- ([micro]g/L)
Parameter ---------------------------
Col. 1 Col. 2 ECDGC FIDGC
----------------------------------------------------------------------------------------------------------------
Nitrobenzene............................................ 3.31 4.31 13.7 3.6
2,6-Dinitrotoluene...................................... 3.52 4.75 0.01 -
Isophorone.............................................. 4.49 5.72 15.7 5.7
2,4-Dinitrotoluene...................................... 5.35 6.54 0.02 -
----------------------------------------------------------------------------------------------------------------
AAColumn 1 conditions: Gas-Chrom Q (80/100 mesh) coated with 1.95% QF-1/1.5% OV-17 packed in a 1.2 m long x 2
mm or 4 mm ID glass column. A 2 mm ID column and nitrogen carrier gas at 44 mL/min flow rate were used when
determining isophorone and nitrobenzene by FIDGC. The column temperature was held isothermal at 85 [deg]C. A 4
mm ID column and 10% methane/90% argon carrier gas at 44 mL/min flow rate were used when determining the
dinitrotoluenes by ECDGC. The column temperature was held isothermal at 145 [deg]C.
AAColumn 2 conditions: Gas-Chrom Q (80/100 mesh) coated with 3% OV-101 packed in a 3.0 m long x 2 mm or 4 mm ID
glass column. A 2 mm ID column and nitrogen carrier gas at 44 mL/min flow rate were used when determining
isophorone and nitrobenzene by FIDGC. The column temperature was held isothermal at 100 [deg]C. A 4 mm ID
column and 10% methane/90% argon carrier gas at 44 mL/min flow rate were used when determining the
dinitrotoluenes by ECDGC. The column temperature was held isothermal at 150 [deg]C.
Table 2--QC Acceptance Criteria--Method 609
----------------------------------------------------------------------------------------------------------------
Test Conc. Range for X
Parameter ([micro]g/ Limit for s ([micro]g/L) Range for
L) ([micro]g/L) P, Ps (%)
----------------------------------------------------------------------------------------------------------------
2,4-Dinitrotoluene........................................ 20 5.1 3.6-22.8 6-125
2,6-Dinitrotoluene........................................ 20 4.8 3.8-23.0 8-126
Isophorone................................................ 100 32.3 8.0-100.0 D-117
Nitrobenzene.............................................. 100 33.3 25.7-100.0 6-118
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 609
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
2,4-Dinitro-
toluene............................................... 0.65C+0.22 0.20X+0.08 0.37X-0.07
2,6-Dinitro-
toluene............................................... 0.66C+0.20 0.19X+0.06 0.36X-0.00
Isophorone............................................. 0.49C+2.93 0.28X+2.77 0.46X+0.31
Nitrobenzene........................................... 0.60C+2.00 0.25X+2.53 0.37X-0.78
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 174]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.029
[[Page 175]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.030
[[Page 176]]
Method 610--Polynuclear Aromatic Hydrocarbons
1. Scope and Application
1.1 This method covers the determination of certain polynuclear
aromatic hydrocarbons (PAH). The following parameters can be determined
by this method:
------------------------------------------------------------------------
Parameter STORET No. CAS No.
------------------------------------------------------------------------
Acenaphthene................................ 34205 83-32-9
Acenaphthylene.............................. 34200 208-96-8
Anthracene.................................. 34220 120-12-7
Benzo(a)anthracene.......................... 34526 56-55-3
Benzo(a)pyrene.............................. 34247 50-32-8
Benzo(b)fluoranthene........................ 34230 205-99-2
Benzo(ghi)perylene.......................... 34521 191-24-2
Benzo(k)fluoranthene........................ 34242 207-08-9
Chrysene.................................... 34320 218-01-9
Dibenzo(a,h)anthracene...................... 34556 53-70-3
Fluoranthene................................ 34376 206-44-0
Fluorene.................................... 34381 86-73-7
Indeno(1,2,3-cd)pyrene...................... 34403 193-39-5
Naphthalene................................. 34696 91-20-3
Phenanthrene................................ 34461 85-01-8
Pyrene...................................... 34469 129-00-0
------------------------------------------------------------------------
1.2 This is a chromatographic method applicable to the determination
of the compounds listed above in municipal and industrial discharges as
provided under 40 CFR 136.1. When this method is used to analyze
unfamiliar samples for any or all of the compounds above, compound
identifications should be supported by at least one additional
qualitative technique. Method 625 provides gas chromatograph/mass
spectrometer (GC/MS) conditions appropriate for the qualitative and
quantitative confirmation of results for many of the parameters listed
above, using the extract produced by this method.
1.3 This method provides for both high performance liquid
chromatographic (HPLC) and gas chromatographic (GC) approaches for the
determination of PAHs. The gas chromatographic procedure does not
adequately resolve the following four pairs of compounds: Anthracene and
phenanthrene; chrysene and benzo(a)anthracene; benzo(b)fluoranthene and
benzo(k)fluoranthene; and dibenzo(a,h) anthracene and indeno (1,2,3-
cd)pyrene. Unless the purpose for the analysis can be served by
reporting the sum of an unresolved pair, the liquid chromatographic
approach must be used for these compounds. The liquid chromatographic
method does resolve all 16 of the PAHs listed.
1.4 The method detection limit (MDL, defined in Section 15.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.5 The sample extraction and concentration steps in this method are
essentially the same as in Methods 606, 608, 609, 611, and 612. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. Selection of the
aliquots must be made prior to the solvent exchange steps of this
method. The analyst is allowed the latitude, under Sections 12 and 13,
to select chromatographic conditions appropriate for the simultaneous
measurement of combinations of these parameters.
1.6 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.7 This method is restricted to use by or under the supervision of
analysts experienced in the use of HPLC and GC systems and in the
interpretation of liquid and gas chromatograms. Each analyst must
demonstrate the ability to generate acceptable results with this method
using the procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and concentrated to a volume of 10 mL or less.
The extract is then separated by HPLC or GC. Ultraviolet (UV) and
fluorescence detectors are used with HPLC to identify and measure the
PAHs. A flame ionization detector is used with GC. \2\
2.2 The method provides a silica gel column cleanup procedure to aid
in the elimination of interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardward that lead to
discrete artifacts and/or elevated baselines in the chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be
[[Page 177]]
substituted for the muffle furnace heating. Thorough rinsing with such
solvents usually eliminates PCB interference. Volumetric ware should not
be heated in a muffle furnace. After drying and cooling, glassware
should be sealed and stored in a clean environment to prevent any
accumulation of dust or other contaminants. Store inverted or capped
with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedure in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
3.3 The extent of interferences that may be encountered using liquid
chromatographic techniques has not been fully assessed. Although the
HPLC conditions described allow for a unique resolution of the specific
PAH compounds covered by this method, other PAH compounds may interfere.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method have not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified
4-6 for the information of the analyst.
4.2 The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: benzo(a)anthracene, benzo(a)pyrene, and dibenzo(a,h)-
anthracene. Primary standards of these toxic compounds should be
prepared in a hood. A NIOSH/MESA approved toxic gas respirator should be
worn when the analyst handles high concentrations of these toxic
compounds.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.4 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.5 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.6 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.7 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.8 Chromatographic column--250 mm long x 10 mm ID, with coarse
frit filter disc at bottom and Teflon stopcock.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 High performance liquid chromatograph (HPLC)--An analytical
system complete with column supplies, high pressure syringes, detectors,
and compatible strip-chart recorder. A data system is recommended for
measuring peak areas and retention times.
5.6.1 Gradient pumping system--Constant flow.
[[Page 178]]
5.6.2 Reverse phase column--HC-ODS Sil-X, 5 micron particle
diameter, in a 25 cm x 2.6 mm ID stainless steel column (Perkin Elmer
No. 089-0716 or equivalent). This column was used to develop the method
performance statements in Section 15. Guidelines for the use of
alternate column packings are provided in Section 12.2.
5.6.3 Detectors--Fluorescence and/or UV detectors. The fluorescence
detector is used for excitation at 280 nm and emission greater than 389
nm cutoff (Corning 3-75 or equivalent). Fluorometers should have
dispersive optics for excitation and can utilize either filter or
dispersive optics at the emission detector. The UV detector is used at
254 nm and should be coupled to the fluorescence detector. These
detectors were used to develop the method performance statements in
Section 15. Guidelines for the use of alternate detectors are provided
in Section 12.2.
5.7 Gas chromatograph--An analytical system complete with
temperature programmable gas chromatograph suitable for on-column or
splitless injection and all required accessories including syringes,
analytical columns, gases, detector, and strip-chart recorder. A data
system is recommended for measuring peak areas.
5.7.1 Column--1.8 m long x 2 mm ID glass, packed with 3% OV-17 on
Chromosorb W-AW-DCMS (100/120 mesh) or equivalent. This column was used
to develop the retention time data in Table 2. Guidelines for the use of
alternate column packings are provided in Section 13.3.
5.7.2 Detector--Flame ionization detector. This detector has proven
effective in the analysis of wastewaters for the parameters listed in
the scope (Section 1.1), excluding the four pairs of unresolved
compounds listed in Section 1.3. Guidelines for the use of alternate
detectors are provided in Section 13.3.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Cyclohexane, methanol, acetone, methylene chloride, pentane--
Pesticide quality or equivalent.
6.4 Acetonitrile--HPLC quality, distilled in glass.
6.5 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.6 Silica gel--100/200 mesh, desiccant, Davison, grade-923 or
equivalent. Before use, activate for at least 16 h at 130 [deg]C in a
shallow glass tray, loosely covered with foil.
6.7 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.7.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in acetonitrile and
dilute to volume in a 10-mL volumetric flask. Larger volumes can be used
at the convenience of the analyst. When compound purity is assayed to be
96% or greater, the weight can be used without correction to calculate
the concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.7.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.7.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with check standards indicates a problem.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish liquid or gas chromatographic operating conditions
equivalent to those given in Table 1 or 2. The chromatographic system
can be calibrated using the external standard technique (Section 7.2) or
the internal standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with acetonitrile. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 5 to 25 [micro]L for HPLC and 2 to 5
[micro]L for GC, analyze each calibration standard according to Section
12 or 13, as appropriate. Tabulate peak height or area responses against
the mass injected. The results can be used to prepare a calibration
curve for each compound. Alternatively, if the ratio of response to
amount injected (calibration factor) is a constant over the working
range (<10% relative standard deviation, RSD), linearity through the
origin can be assumed and the average ratio or calibration factor can be
used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the
[[Page 179]]
compounds of interest. The analyst must further demonstrate that the
measurement of the internal standard is not affected by method or matrix
interferences. Because of these limitations, no internal standard can be
suggested that is applicable to all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with acetonitrile. One of the standards should be
at a concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 5 to 25 [micro]L for HPLC and 2 to 5
[micro]L for GC, analyze each calibration standard according to Section
12 or 13, as appropriate. Tabulate peak height or area responses against
concentration for each compound and internal standard. Calculate
response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.113
Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, the test must
be repeated using a fresh calibration standard. Alternatively, a new
calibration curve must be prepared for that compound.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, 12.2, and 13.3) to improve the separations or lower
the cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at the following concentrations in
acetonitrile: 100 [micro]g/mL of any
[[Page 180]]
of the six early-eluting PAHs (naphthalene, acenaphthylene,
acenaphthene, fluorene, phenanthrene, and anthracene); 5 [micro]g/mL of
benzo(k)fluoranthene; and 10 [micro]g/mL of any of the other PAHs. The
QC check sample concentrate must be obtained from the U.S. Environmental
Protection Agency, Environmental Monitoring and Support Laboratory in
Cincinnati, Ohio, if available. If not available from that source, the
QC check sample concentrate must be obtained from another external
source. If not available from either source above, the QC check sample
concentrate must be prepared by the laboratory using stock standards
prepared independently from those used for calibration.
8.2.2 Using a pipet, prepare QC check samples at the test
concentrations shown in Table 3 by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 3. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Table 3 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.2.
8.2.6.2 Beginning with Section 8.2.2, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compounds of interest beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at the test concentration in Section 8.2.2 or 1 to 5
times higher than the background concentration determined in Section
8.3.2, whichever concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none, (2) the larger of either 5 times higher than the expected
background concentration or the test concentration in Section 8.2.2.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100 (A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 3. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than the test
concentration in Section 8.2.2, the analyst must use either the QC
acceptance criteria in Table 3, or optional QC acceptance criteria
calculated for the specific spike concentration. To calculate optional
acceptance criteria for the recovery of a parameter: (1) Calculate
accuracy (X') using the equation in Table 4, substituting the spike
concentration (T) for C; (2) calculate overall precision (S') using the
equation in Table 4, substituting X' for X; (3) calculate the range for
recovery at the spike concentration as (100 X'/T)2.44(100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter
[[Page 181]]
that failed the critiera must be analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory. If the entire list of parameters in Table 3 must be measured
in the sample in Section 8.3, the probability that the analysis of a QC
check standard will be required is high. In this case the QC check
standard should be routinely analyzed with the spike sample.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
3. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If P=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \8\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction. PAHs are known to be light
sensitive; therefore, samples, extracts, and standards should be stored
in amber or foil-wrapped bottles in order to minimize photolytic
decomposition. Fill the sample bottles and, if residual chlorine is
present, add 80 mg of sodium thiosulfate per liter of sample and mix
well. EPA Methods 330.4 and 330.5 may be used for measurement of
residual chlorine. \9\ Field test kits are available for this purpose.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
[[Page 182]]
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.7 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of methylene chloride. A
5-mL syringe is recommended for this operation. Stopper the concentrator
tube and store refrigerated if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial and protected
from light. If the sample extract requires no further cleanup, proceed
with gas or liquid chromatographic analysis (Section 12 or 13). If the
sample requires further cleanup, proceed to Section 11.
10.8 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use the procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the methods as revised
to incorporate the cleanup procedure.
11.2 Before the silica gel cleanup technique can be utilized, the
extract solvent must be exchanged to cyclohexane. Add 1 to 10 mL of the
sample extract (in methylene chloride) and a boiling chip to a clean K-D
concentrator tube. Add 4 mL of cyclohexane and attach a two-ball micro-
Snyder column. Prewet the column by adding 0.5 mL of methylene chloride
to the top. Place the micro-K-D apparatus on a boiling (100 [deg]C)
water bath so that the concentrator tube is partially immersed in the
hot water. Adjust the vertical position of the apparatus and the water
temperature as required to complete concentration in 5 to 10 min. At the
proper rate of distillation the balls of the column will actively
chatter but the chambers will not flood. When the apparent volume of the
liquid reaches 0.5 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min. Remove the micro-Snyder column and rinse
its lower joint into the concentrator tube with a minimum amount of
cyclohexane. Adjust the extract volume to about 2 mL.
11.3 Silica gel column cleanup for PAHs:
11.3.1 Prepare a slurry of 10 g of activiated silica gel in
methylene chloride and place this into a 10-mm ID chromatographic
column. Tap the column to settle the silica gel and elute the methylene
chloride. Add 1 to 2 cm of anhydrous sodium sulfate to the top of the
silica gel.
11.3.2 Preelute the column with 40 mL of pentane. The rate for all
elutions should be about 2 mL/min. Discard the eluate and just prior to
exposure of the sodium sulfate layer to the air, transfer the 2-mL
cyclohexane sample extract onto the column using an additional 2 mL
cyclohexane to complete the transfer. Just prior to exposure of the
sodium sulfate layer to the air, add 25 mL of pentane and continue the
elution of the column. Discard this pentane eluate.
11.3.3 Next, elute the column with 25 mL of methylene chloride/
pentane (4+6)(V/V) into a 500-mL K-D flask equipped with a 10-mL
concentrator tube. Concentrate the collected fraction to less than 10 mL
as in Section 10.6. When the apparatus is cool, remove the Snyder column
and rinse the flask and its lower joint with pentane. Proceed with HPLC
or GC analysis.
12. High Performance Liquid Chromatography
12.1 To the extract in the concentrator tube, add 4 mL of
acetonitrile and a new boiling chip, then attach a two-ball micro-Snyder
column. Concentrate the solvent as in Section 10.6, except set the water
bath at 95 to 100 [deg]C. When the apparatus is cool, remove the micro-
Snyder column and rinse its lower joint into the concentrator tube with
about 0.2 mL of acetonitrile. Adjust the extract volume to 1.0 mL.
12.2 Table 1 summarizes the recommended operating conditions for the
HPLC. Included in this table are retention times, capacity factors, and
MDL that can be achieved under these conditions. The UV detector is
recommended for the determination of naphthalene, acenaphthylene,
acenapthene, and
[[Page 183]]
fluorene and the fluorescence detector is recommended for the remaining
PAHs. Examples of the separations achieved by this HPLC column are shown
in Figures 1 and 2. Other HPLC columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
12.3 Calibrate the system daily as described in Section 7.
12.4 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the instrument.
12.5 Inject 5 to 25 [micro]L of the sample extract or standard into
the HPLC using a high pressure syringe or a constant volume sample
injection loop. Record the volume injected to the nearest 0.1 [micro]L,
and the resulting peak size in area or peak height units. Re-equilibrate
the HPLC column at the initial gradient conditions for at least 10 min
between injections.
12.6 Identify the parameters in the sample by comparing the
retention time of the peaks in the sample chromatogram with those of the
peaks in standard chromatograms. The width of the retention time window
used to make identifications should be based upon measurements of actual
retention time variations of standards over the course of a day. Three
times the standard deviation of a retention time for a compound can be
used to calculate a suggested window size; however, the experience of
the analyst should weigh heavily in the interpretation of chromatograms.
12.7 If the response for a peak exceeds the working range of the
system, dilute the extract with acetonitrile and reanalyze.
12.8 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Gas Chromatography
13.1 The packed column GC procedure will not resolve certain
isomeric pairs as indicated in Section 1.3 and Table 2. The liquid
chromatographic procedure (Section 12) must be used for these
parameters.
13.2 To achieve maximum sensitivity with this method, the extract
must be concentrated to 1.0 mL. Add a clean boiling chip to the
methylene chloride extract in the concentrator tube. Attach a two-ball
micro-Snyder column. Prewet the micro-Snyder column by adding about 0.5
mL of methylene chloride to the top. Place the micro-K-D apparatus on a
hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water. Adjust the vertical position of the
apparatus and the water temperature as required to complete the
concentration in 5 to 10 min. At the proper rate of distillation the
balls will actively chatter but the chambers will not flood. When the
apparent volume of liquid reaches 0.5 mL, remove the K-D apparatus and
allow it to drain and cool for at least 10 min. Remove the micro-Snyder
column and rinse its lower joint into the concentrator tube with a
minimum amount of methylene chloride. Adjust the final volume to 1.0 mL
and stopper the concentrator tube.
13.3 Table 2 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times that were
obtained under these conditions. An example of the separations achieved
by this column is shown in Figure 3. Other packed or capillary (open-
tubular) columns, chromatographic conditions, or detectors may be used
if the requirements of Section 8.2 are met.
13.4 Calibrate the gas chromatographic system daily as described in
Section 7.
13.5 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatograph.
13.6 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \10\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, and
the resulting peak size in area or peak height units.
13.7 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
13.8 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
13.9 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
14. Calculations
14.1 Determine the concentration of individual compounds in the
sample.
14.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[[Page 184]]
[GRAPHIC] [TIFF OMITTED] TC15NO91.114
Equation 2
where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([micro]L).
Vt=Volume of total extract ([micro]L).
Vs=Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.115
Equation 3
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract
([micro]g).
Vo=Volume of water extracted (L).
14.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
15. Method Performance
15.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \11\ Similar
results were achieved using representative wastewaters. MDL for the GC
approach were not determined. The MDL actually achieved in a given
analysis will vary depending on instrument sensitivity and matrix
effects.
15.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 8 x MDL to 800 x MDL \11\ with the following
exception: benzo(ghi)perylene recovery at 80 x and 800 x MDL were low
(35% and 45%, respectively).
15.3 This method was tested by 16 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 0.1 to 425 [micro]g/L. \12\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 4.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Polynuclear Aromatic Hydrocarbons in
Industrial and Municipal Wastewaters,'' EPA 600/4-82-025, National
Technical Information Service, PB82-258799, Springfield, Virginia 22161,
June 1982.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
9. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
10. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
11. Cole, T., Riggin, R., and Glaser, J. ``Evaluation of Method
Detection Limits and Analytical Curve for EPA Method 610--PNAs,''
International Symposium on Polynuclear Aromatic Hydrocarbons, 5th,
Battelle's Columbus Laboratories, Columbus, Ohio (1980).
12. ``EPA Method Study 20, Method 610 (PNA's),'' EPA 600/4-84-063,
National Technical Information Service, PB84-211614, Springfield,
Virginia 22161, June 1984.
[[Page 185]]
Table 1--High Performance Liquid Chromatography Conditions and Method
Detection Limits
------------------------------------------------------------------------
Method
Retention Column detection
Parameter time capacity limit
(min) factor ([micro]g/
(k') L) \a\
------------------------------------------------------------------------
Naphthalene........................... 16.6 12.2 1.8
Acenaphthylene........................ 18.5 13.7 2.3
Acenaphthene.......................... 20.5 15.2 1.8
Fluorene.............................. 21.2 15.8 0.21
Phenanthrene.......................... 22.1 16.6 0.64
Anthracene............................ 23.4 17.6 0.66
Fluoranthene.......................... 24.5 18.5 0.21
Pyrene................................ 25.4 19.1 0.27
Benzo(a)anthracene.................... 28.5 21.6 0.013
Chrysene.............................. 29.3 22.2 0.15
Benzo(b)fluoranthene.................. 31.6 24.0 0.018
Benzo(k)fluoranthene.................. 32.9 25.1 0.017
Benzo(a)pyrene........................ 33.9 25.9 0.023
Dibenzo(a,h)anthracene................ 35.7 27.4 0.030
Benzo(ghi)perylene.................... 36.3 27.8 0.076
Indeno(1,2,3-cd)pyrene................ 37.4 28.7 0.043
------------------------------------------------------------------------
AAAHPLC column conditions: Reverse phase HC-ODS Sil-X, 5 micron
particle size, in a 25 cm x 2.6 mm ID stainless steel column.
Isocratic elution for 5 min. using acetonitrile/water (4+6), then
linear gradient elution to 100% acetonitrile over 25 min. at 0.5 mL/
min flow rate. If columns having other internal diameters are used,
the flow rate should be adjusted to maintain a linear velocity of 2 mm/
sec.
\a\ The MDL for naphthalene, acenaphthylene, acenaphthene, and fluorene
were determined using a UV detector. All others were determined using
a fluorescence detector.
Table 2--Gas Chromatographic Conditions and Retention Times
------------------------------------------------------------------------
Retention
Parameter time (min)
------------------------------------------------------------------------
Naphthalene................................................. 4.5
Acenaphthylene.............................................. 10.4
Acenaphthene................................................ 10.8
Fluorene.................................................... 12.6
Phenanthrene................................................ 15.9
Anthracene.................................................. 15.9
Fluoranthene................................................ 19.8
Pyrene...................................................... 20.6
Benzo(a)anthracene.......................................... 24.7
Chrysene.................................................... 24.7
Benzo(b)fluoranthene........................................ 28.0
Benzo(k)fluoranthene........................................ 28.0
Benzo(a)pyrene.............................................. 29.4
Dibenzo(a,h)anthracene...................................... 36.2
Indeno(1,2,3-cd)pyrene...................................... 36.2
Benzo(ghi)perylene.......................................... 38.6
------------------------------------------------------------------------
GC Column conditions: Chromosorb W-AW-DCMS (100/120 mesh) coated with 3%
OV-17 packed in a 1.8 x 2 mm ID glass column with nitrogen carrier gas
at 40 mL/min. flow rate. Column temperature was held at 100 [deg]C for
4 min., then programmed at 8 [deg]C/min. to a final hold at 280
[deg]C.
Table 3--QC Acceptance Criteria--Method 610
----------------------------------------------------------------------------------------------------------------
Range for X
Test conc. Limit for s ([micro]g/ Range for
Parameter ([micro]g/ ([micro]g/ L) P, Ps (%)
L) L)
----------------------------------------------------------------------------------------------------------------
Acenaphthene................................................ 100 40.3 D-105.7 D-124
Acenaphthylene.............................................. 100 45.1 22.1-112.1 D-139
Anthracene.................................................. 100 28.7 11.2-112.3 D-126
Benzo(a)anthracene.......................................... 10 4.0 3.1-11.6 12-135
Benzo(a)pyrene.............................................. 10 4.0 0.2-11.0 D-128
Benzo(b)fluor-anthene....................................... 10 3.1 1.8-13.8 6-150
Benzo(ghi)perylene.......................................... 10 2.3 D-10.7 D-116
Benzo(k)fluo-ranthene....................................... 5 2.5 D-7.0 D-159
Chrysene.................................................... 10 4.2 D-17.5 D-199
Dibenzo(a,h)an-thracene..................................... 10 2.0 0.3-10.0 D-110
Fluoranthene................................................ 10 3.0 2.7-11.1 14-123
Fluorene.................................................... 100 43.0 D-119 D-142
Indeno(1,2,3-cd)pyrene...................................... 10 3.0 1.2-10.0 D-116
Naphthalene................................................. 100 40.7 21.5-100.0 D-122
Phenanthrene................................................ 100 37.7 8.4-133.7 D-155
Pyrene...................................................... 10 3.4 1.4-12.1 D-140
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 4. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 4.
[[Page 186]]
Table 4--Method Accuracy and Precision as Functions of Concentration--Method 610
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Acenaphthene.................................................... 0.52C + 0.54 0.39X + 0.76 0.53X + 1.32
Acenaphthylene.................................................. 0.69C - 1.89 0.36X + 0.29 0.42X + 0.52
Anthracene...................................................... 0.63C - 1.26 0.23X + 1.16 0.41X + 0.45
Benzo(a)anthracene.............................................. 0.73C + 0.05 0.28X + 0.04 0.34X + 0.02
Benzo(a)pyrene.................................................. 0.56C + 0.01 0.38X - 0.01 0.53X - 0.01
Benzo(b)fluoranthene............................................ 0.78C + 0.01 0.21X + 0.01 0.38X - 0.00
Benzo(ghi)perylene.............................................. 0.44C + 0.30 0.25X + 0.04 0.58X + 0.10
Benzo(k)fluoranthene............................................ 0.59C + 0.00 0.44X - 0.00 0.69X + 0.01
Chrysene........................................................ 0.77C - 0.18 0.32X - 0.18 0.66X - 0.22
Dibenzo(a,h)anthracene.......................................... 0.41C + 0.11 0.24X + 0.02 0.45X + 0.03
Fluoranthene.................................................... 0.68C + 0.07 0.22X + 0.06 0.32X + 0.03
Fluorene........................................................ 0.56C - 0.52 0.44X - 1.12 0.63X - 0.65
Indeno(1,2,3-cd)pyrene.......................................... 0.54C + 0.06 0.29X + 0.02 0.42X + 0.01
Naphthalene..................................................... 0.57C - 0.70 0.39X - 0.18 0.41X + 0.74
Phenanthrene.................................................... 0.72C - 0.95 0.29X + 0.05 0.47X - 0.25
Pyrene.......................................................... 0.69C - 0.12 0.25X + 0.14 0.42X - 0.00
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[GRAPHIC] [TIFF OMITTED] TC02JY92.031
[[Page 187]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.032
[[Page 188]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.033
Method 611--Haloethers
1. Scope and Application
1.1 This method covers the determination of certain haloethers. The
following parameters can be determined by this method:
------------------------------------------------------------------------
Parameter STORET No. CAS No.
------------------------------------------------------------------------
Bis(2-chloroethyl) ether...................... 34273 111-44-4
Bis(2-chloroethoxy) methane................... 34278 111-91-1
Bis(2-chloroisopropyl) ether.................. 34283 108-60-1
4-Bromophenyl phenyl ether.................... 34636 101-55-3
4-Chlorophenyl phenyl either.................. 34641 7005-72-3
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of the compounds listed above in municipal and industrial
discharges as provided under 40 CFR 136.1. When this method is used to
analyze unfamiliar samples for any or all of the compounds above,
compound identifications should be supported by at least one additional
qualitative technique. This method describes analytical conditions for a
second gas chromatographic column that can be used to confirm
measurements made with the primary column. Method 625 provides gas
chromatograph/mass spectrometer (GC/MS) conditions appropriate for the
qualitative and quantitative confirmation of results for all of the
parameters listed above, using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 The sample extraction and concentration steps in this method are
essentially the same as in Methods 606, 608, 609, and 612. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. The analyst is
allowed the latitude, under Section 12, to select
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chromatographic conditions appropriate for the simultaneous measurement
of combinations of these parameters.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and exchanged to hexane during concentration
to a volume of 10 mL or less. The extract is separated by gas
chromatography and the parameters are then measured with a halide
specific detector. \2\
2.2 The method provides a Florisil column cleanup procedure to aid
in the elimination of interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed be detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such a PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedure in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
3.3 Dichlorobenzenes are known to coelute with haloethers under some
gas chromatographic conditions. If these materials are present together
in a sample, it may be necessary to analyze the extract with two
different column packings to completely resolve all of the compounds.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified
4-6 for the information of the analyst.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating
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flow meter is required to collect flow proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Chromatographic column--400 mm long x 19 mm ID, with Teflon
stopcock and coarse frit filter disc at bottom (Kontes K-420540-0224 or
equivalent).
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2[deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, gases, detector, and strip-chart recorder. A data system is
recommended for measuring peak areas.
5.6.1 Column 1--1.8 m long x 2 mm ID glass, packed with 3% SP-1000
on Supelcoport (100/120 mesh) or equivalent. This column was used to
develop the method performance statements in Section 14. Guidelines for
the use of alternate column packings are provided in Section 12.1.
5.6.2 Column 2--1.8 m long x 2 mm ID glass, packed with 2,6-
diphenylene oxide polymer (60/80 mesh), Tenax, or equivalent.
5.6.3 Detector--Halide specific detector: electrolytic conductivity
or microcoulometric. These detectors have proven effective in the
analysis of wastewaters for the parameters listed in the scope (Section
1.1). The Hall conductivity detector was used to develop the method
performance statements in Section 14. Guidelines for the use of
alternate detectors are provided in Section 12.1. Although less
selective, an electron capture detector is an acceptable alternative.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Acetone, hexane, methanol, methylene chloride, petroleum ether
(boiling range 30-60 [deg]C)--Pesticide quality or equivalent.
6.4 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.5 Florisil--PR Grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in the dark in glass containers with ground glass
stoppers or foil-lined screw caps. Before use, activate each batch at
least 16 h at 130 [deg]C in a foil-covered glass container and allow to
cool.
6.6 Ethyl ether--Nanograde, redistilled in glass if necessary.
6.6.1 Ethyl ether must be shown to be free of peroxides before it is
used as indicated by EM Laboratories Quant test strips. (Available from
Scientific Products Co., Cat. No. P1126-8, and other suppliers.)
6.6.2 Procedures recommended for removal of peroxides are provided
with the test strips. After cleanup, 20 mL of ethyl alcohol preservative
must be added to each liter of ether.
6.7 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutions can be prepared from pure standard materials or
purchased as certified solutions.
6.7.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in acetone and dilute
to volume in a 10-mL volumetric flask. Larger volumes can be used at the
convenience of the analyst. When compound purity is assayed to be 96% or
greater, the weight can be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.7.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.7.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with check standards indicates a problem.
6.8 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatographic operating conditions equivalent to
those given in Table 1. The gas chromatographic system
[[Page 191]]
can be calibrated using the external standard technique (Section 7.2) or
the internal standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with hexane. One of the external standards should be at a concentration
near, but above, the MDL (Table 1) and the other concentrations should
correspond to the expected range of concentrations found in real samples
or should define the working range of the detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with hexane. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.116
Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 The cleanup procedure in Section 11 utilizes Florisil column
chromatography. Florisil from different batches or sources may vary in
adsorptive capacity. To standardize the amount of Florisil which is
used, the use of lauric acid value \7\ is suggested. The referenced
procedure determines the adsorption from hexane solution of lauric acid
(mg) per g of Florisil. The amount of Florisil to be used for each
column is calculated by dividing 110 by this ratio and multiplying by 20
g.
7.6 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
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8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 100
[micro]g/mL in acetone. The QC check sample concentrate must be obtained
from the U.S. Environmental Protection Agency, Environmental Monitoring
and Support Laboratory in Cincinnati, Ohio, if available. If not
available from that source, the QC check sample concentrate must be
obtained from another external source. If not available from either
source above, the QC check sample concentrate must be prepared by the
laboratory using stock standards prepared independently from those used
for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
100 [micro]g/L by adding 1.00 mL of QC check sample concentrate to each
of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter. Locate and correct the
source of the problem and repeat the test for all parameters of interest
beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1. The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 100 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or 100 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\8\ If spiking was performed at a concentration lower than 100 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 2, or
optional QC
[[Page 193]]
acceptance criteria calculated for the specific spike concentration. To
calculate optional acceptance criteria for the recovery of a parameter:
(1) Calculate accuracy (X') using the equation in Table 3, substituting
the spike concentration (T) for C; (2) calculate overall precision (S')
using the equation in Table 3, substituting X' for X; (3) calculate the
range for recovery at the spike concentration as (100 X'/T)2.44(100 S'/T)%. \8\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 m/L of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If P=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \9\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction. Fill the sample bottles and, if
residual chlorine is present, add 80 mg of sodium thiosulfate per liter
of sample and mix well. EPA Methods 330.4 and 330.5 may be used for
measurement of residual chlorine. \10\ Field test kits are available for
this purpose.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 Add 60 mL methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2 min
with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time,
[[Page 194]]
combining the extracts in the Erlenmeyer flask. Perform a third
extraction in the same manner.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
Note: Some of the haloethers are very volatile and significant
losses will occur in concentration steps if care is not exercised. It is
important to maintain a constant gentle evaporation rate and not to
allow the liquid volume to fall below 1 to 2 mL before removing the K-D
apparatus from the hot water bath.
10.7 Momentarily remove the Snyder column, add 50 mL of hexane and a
new boiling chip, and reattach the Snyder column. Raise the temperature
of the water bath to 85 to 90 [deg]C. Concentrate the extract as in
Section 10.6, except use hexane to prewet the column. The elapsed time
of concentration should be 5 to 10 min.
10.8 Remove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL
syringe is recommended for this operation. Stopper the concentrator tube
and store refrigerated if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial. If the sample
extract requires no further cleanup, proceed with gas chromatographic
analysis (Section 12). If the sample requires further cleanup, proceed
to Section 11.
10.9 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use the procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the method as revised
to incorporate the cleanup procedure.
11.2 Florisil column cleanup for haloethers:
11.2.1 Adjust the sample extract volume to 10 mL.
11.2.2 Place a weight of Florisil (nominally 20 g) predetermined by
calibration (Section 7.5), into a chromatographic column. Tap the column
to settle the Florisil and add 1 to 2 cm of anhydrous sodium sulfate to
the top.
11.2.3 Preelute the column with 50 to 60 mL of petroleum ether.
Discard the eluate and just prior to exposure of the sodium sulfate
layer to the air, quantitatively transfer the sample extract onto the
column by decantation and subsequent petroleum ether washings. Discard
the eluate. Just prior to exposure of the sodium sulfate layer to the
air, begin eluting the column with 300 mL of ethyl ether/petroleum ether
(6+94) (V/V). Adjust the elution rate to approximately 5 mL/min and
collect the eluate in a 500-mL K-D flask equipped with a 10-mL
concentrator tube. This fraction should contain all of the haloethers.
11.2.4 Concentrate the fraction as in Section 10.6, except use
hexane to prewet the column. When the apparatus is cool, remove the
Snyder column and rinse the flask and its lower joint into the
concentrator tube with hexane. Adjust the volume of the cleaned up
extract to 10 mL with hexane and analyze by gas chromatography (Section
12).
12. Gas Chromatography
12.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Examples of the separations
achieved by Columns 1 and 2 are shown in Figures 1 and 2, respectively.
Other packed or capillary (open-tubular) columns, chromatographic
conditions, or detectors may be used if the requirements of Section 8.2
are met.
12.2 Calibrate the system daily as described in Section 7.
12.3 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
thoroughly immediately before injection into the gas chromatrograph.
[[Page 195]]
12.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush technique. \11\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, the
total extract volume, and the resulting peak size in area or peak height
units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weight heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.117
Equation 2
where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([micro]L).
Vt=Volume of total extract ([micro]L).
Vs=Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.118
Equation 3
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract
([micro]g).
Vo=Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \12\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 4 x MDL to 1000 x MDL. \12\
14.3 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 1.0 to 626 [micro]/L. \12\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Haloethers in Industrial and Municipal
Wastewaters,'' EPA 600/4-81-062, National Technical Information Service,
PB81-232290, Springfield, Virginia 22161, July 1981.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constitutents,'' American Society for Testing and Materials,
Philadelphia.
4. ``Carcinogens--Working Carcinogens, '' Department of Health,
Education, and Welfare, Public Health Services, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Mills., P.A. ``Variation of Florisil Activity: Simple Method for
Measuring Absorbent Capacity and Its Use in Standardizing
[[Page 196]]
Florisil Columns,'' Journal of the Association of Official Analytical
Chemists, 51, 29 (1968).
8. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
9. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
10. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
11. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
12. ``EPA Method Study 21, Method 611, Haloethers,'' EPA 600/4-84-
052, National Technical Information Service, PB84-205939, Springfield,
Virginia 22161, June 1984.
Table 1--Chromatographic Conditions and Methods Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
---------------------- detection
Parameters limit
Column 1 Column 2 ([micro]/
L)
------------------------------------------------------------------------
Bis(2-chloroisopropyl) ether........... 8.4 9.7 0.8
Bis(2-chloroethyl) ether............... 9.3 9.1 0.3
Bis(2-chloroethoxy) methane............ 13.1 10.0 0.5
4-Chlorophenyl ether................... 19.4 15.0 3.9
4-Bromophenyl phenyl ether............. 21.2 16.2 2.3
------------------------------------------------------------------------
AColumn 1 conditions: Supelcoport (100/120 mesh) coated with 3% SP-1000
packed in a 1.8 m long x 2 mm ID glass column with helium carrier gas
at 40 mL/min. flow rate. Column temperature held at 60 [deg]C for 2
min. after injection then programmed at 8 [deg]C/min. to 230 [deg]C
and held for 4 min. Under these conditions the retention time for
Aldrin is 22.6 min.
AColumn 2 conditions: Tenax-GC (60/80 mesh) packed in a 1.8 m long x
2mm ID glass column with helium carrier gas at 40 mL/min. flow rate.
Column temperature held at 150 [deg]C for 4 min. after injection then
programmed at 16 [deg]C/min. to 310 [deg]C. Under these conditions the
retention time for Aldrin is 18.4 min.
Table 2--QC Acceptance Criteria--Method 611
----------------------------------------------------------------------------------------------------------------
Range for X
Test conc. Limit for s ([micro]g/ Range for
Parameter ([micro]g/ ([micro]g/L) L) P, Ps
L) percent
----------------------------------------------------------------------------------------------------------------
Bis (2-chloroethyl)ether................................... 100 26.3 26.3-136.8 11-152
Bis (2-chloroethoxy)methane................................ 100 25.7 27.3-115.0 12-128
Bis (2-chloroisopropyl)ether............................... 100 32.7 26.4-147.0 9-165
4-Bromophenyl phenyl ether................................. 100 39.3 7.6 -167.5 D-189
4-Chlorophenyl phenyl ether................................ 100 30.7 15.4-152.5 D-170
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 611
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst Overall
Parameter recovery, X' precision, sr' precision, S'
([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Bis(2-chloroethyl) ether........................................ 0.81C+0.54 0.19X+0.28 0.35X+0,36
Bis(2-chloroethoxy) methane..................................... 0.71C+0.13 0.20X+0.15 0.33X+0.11
Bis(2-chloroisopropyl) ether.................................... 0.85C+1.67 0.20X+1.05 0.36X+0.79
4-Bromophenyl phenyl ether...................................... 0.85C+2.55 0.25X+0.21 0.47X+0.37
4-Chlorophenyl phenyl ether..................................... 0.82C+1.97 0.18X+2.13 0.41X+0.55
----------------------------------------------------------------------------------------------------------------
X' = Expected recovery for one or more measuremelts of a sample containing a concentration of C, in [micro]g/L.
sr' = Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S' = Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C =True value for the concentration, in [micro]g/L.
X = Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
[[Page 197]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.034
[[Page 198]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.035
Method 612--Chlorinated Hydrocarbons
1. Scope and Application
1.1 This method covers the determination of certain chlorinated
hydrocarbons. The following parameters can be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
2-Chloronaphthalene.............................. 34581 91-58-7
1,2-Dichlorobenzene.............................. 34536 95-50-1
1,3-Dichlorobenzene.............................. 34566 541-73-1
1,4-Dichlorobenzene.............................. 34571 106-46-7
Hexachlorobenzene................................ 39700 118-74-1
Hexachlorobutadiene.............................. 34391 87-68-3
Hexachlorocyclopentadiene........................ 34386 77-47-4
Hexachloroethane................................. 34396 67-72-1
[[Page 199]]
1,2,4-Trichlorobenzene........................... 34551 120-82-1
------------------------------------------------------------------------
1.2 This is a gas chromatographic (GC) method applicable to the
determination of the compounds listed above in municipal and industrial
discharges as provided under 40 CFR 136.1. When this method is used to
analyze unfamiliar samples for any or all of the compounds above,
compound identifications should be supported by at least one additional
qualitative technique. This method describes a second gas
chromatographic column that can be used to confirm measurements made
with the primary column. Method 625 provides gas chromatograph/mass
spectrometer (GC/MS) conditions appropriate for the qualitative and
quantitative confirmation of results for all of the parameters listed
above, using the extract produced by this method.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.4 The sample extraction and concentration steps in this method are
essentially the same as in Methods 606, 608, 609, and 611. Thus, a
single sample may be extracted to measure the parameters included in the
scope of each of these methods. When cleanup is required, the
concentration levels must be high enough to permit selecting aliquots,
as necessary, to apply appropriate cleanup procedures. The analyst is
allowed the latitude, under Section 12, to select chromatographic
conditions appropriate for the simultaneous measurement of combinations
of these parameters.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph and in the
interpretation of gas chromatograms. Each analyst must demonstrate the
ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is extracted
with methylene chloride using a separatory funnel. The methylene
chloride extract is dried and exchanged to hexane during concentration
to a volume of 10 mL or less. The extract is separated by gas
chromatography and the parameters are then measured with an electron
capture detector. \2\
2.2 The method provides a Florisil column cleanup procedure to aid
in the elimination of interferences that may be encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in gas chromatograms. All
of these materials must be routinely demonstrated to be free from
interferences under the conditions of the analysis by running laboratory
reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled. The
cleanup procedure in Section 11 can be used to overcome many of these
interferences, but unique samples may require additional cleanup
approaches to achieve the MDL listed in Table 1.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all
[[Page 200]]
personnel involved in the chemical analysis. Additional references to
laboratory safety are available and have been identified 4-6
for the information of the analyst.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1cL or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, approximately 400 mm
long x 19 mm ID, with coarse frit filter disc.
5.2.3 Chromatographic column--300 long x 10 mm ID, with Teflon
stopcock and coarse frit filter disc at bottom.
5.2.4 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.5 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.6 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.7 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 Gas chromatograph--An analytical system complete with gas
chromatograph suitable for on-column injection and all required
accessories including syringes, analytical columns, gases, detector, and
strip-chart recorder. A data system is recommended for measuring peak
areas.
5.6.1 Column 1--1.8 m long x 2 mm ID glass, packed with 1% SP-1000
on Supelcoport (100/120 mesh) or equivalent. Guidelines for the use of
alternate column packings are provide in Section 12.1.
5.6.2 Column 2--1.8 m long x2 mm ID glass, packed with 1.5% OV-1/
2.4% OV-225 on Supelcoport (80/100 mesh) or equivalent. This column was
used to develop the method performance statements in Section 14.
5.6.3 Detector--Electron capture detector. This detector has proven
effective in the analysis of wastewaters for the parameters listed in
the scope (Section 1.1), and was used to develop the method performance
statements in Section 14. Guidelines for the use of alternate detectors
are provided in Section 12.1.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Acetone, hexane, isooctane, methanol, methylene chloride,
petroleum ether (boiling range 30 to 60 [deg]C)--Pesticide quality or
equivalent.
6.3 Sodium sulfate--(ACS) Granular, anhydrous. Purify heating at 400
[deg]C for 4 h in a shallow tray.
6.4 Florisil--PR grade (60/100 mesh). Purchase activated at 1250
[deg]F and store in the dark in glass containers with ground glass
stoppers or foil-lined screw caps. Before use, activate each batch at
least 16 h at 130 [deg]C in a foil-covered glass container and allow to
cool.
6.5 Stock standard solution (1.00 [micro]g/[micro]L)--Stock standard
solutions can be prepared from pure standard materials or purchased as
certified solutions.
6.5.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in isooctane and dilute
to volume in a 120-mL volumetric flask. Larger volumes can be used at
the convenience of the analyst. When compound purity is assayed to be
96% or greater, the weight can be used without correction to calculate
the concentration of the stock standard. Commercially prepared stock
standards can be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.5.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
[[Page 201]]
6.5.3 Stock standard solutions must be replaced after six months, or
sooner if comparision with check standards indicates a problem.
6.6 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatographic operating conditions equivalent to
those given in Table 1. The gas chromatographic system can be calibrated
using the external standard technique (Section 7.2) or the internal
standard technique (Section 7.3).
7.2 External standard calibration procedure:
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask and diluting to volume
with isooctane. One of the external standards should be at a
concentration near, but above, the MDL (Table 1) and the other
concentrations should correspond to the expected range of concentrations
found in real samples or should define the working range of the
detector.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against the mass injected. The results can be used to prepare
a calibration curve for each compound. Alternatively, if the ratio of
response to amount injected (calibration factor) is a constant over the
working range (<10% relative standard deviation, RSD), linearity through
the origin can be assumed and the average ratio or calibration factor
can be used in place of a calibration curve.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select one or more internal standards that are similar
in analytical behavior to the compounds of interest. The analyst must
further demonstrate that the measurement of the internal standard is not
affected by method or matrix interferences. Because of these
limitations, no internal standard can be suggested that is applicable to
all samples.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding volumes of
one or more stock standards to a volumetric flask. To each calibration
standard, add a known constant amount of one or more internal standards,
and dilute to volume with isooctane. One of the standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the detector.
7.3.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 12 and tabulate peak height or area
responses against concentration for each compound and internal standard.
Calculate response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.119
Equation 1
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<10% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve, calibration factor, or RF must be
verified on each working day by the measurement of one or more
calibration standards. If the response for any parameter varies from the
predicted response by more than 15%, a new
calibration curve must be prepared for that compound.
7.5 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When the results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
[[Page 202]]
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.4, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such modification is made to the method,
the analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at the following concentrations in
acetone: Hexachloro-substituted parameters, 10 [micro]g/mL; any other
chlorinated hydrocarbon, 100 [micro]g/mL. The QC check sample
concentrate must be obtained from the U.S. Environmental Protection
Agency, Environmental Monitoring and Support Laboratory in Cincinnati,
Ohio, if available. If not available from that source, the QC check
sample concentrate must be obtained from another external source. If not
available from either source above, the QC check sample concentrate must
be prepared by the laboratory using stock standards prepared
independently from those used for calibration.
8.2.2 Using a pipet, prepare QC check samples at the test
concentrations shown in Table 2 by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 2. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Table 2 presents a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.2.
8.2.6.2 Beginning with Section 8.2.2, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compounds of interest beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spike sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at the test concentration in Section 8.2.2 or 1 to 5
times higher than the background concentration determined in Section
8.3.2, whichever concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none by (2) the larger of either 5 times higher than the expected
background concentration or the test concentration in Section 8.2.2.
[[Page 203]]
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. In necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100 (A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than the test
concentration in Section 8.2.2, the analyst must use either the QC
acceptance criteria in Table 2, or optional QC acceptance criteria
calculated for the specific spike concentration. To calculate optional
acceptance criteria for the recovery of a parameter: (1) Calculate
accuracy (X') using the equation in Table 3, substituting the spike
concentration (T) for C; (2) calculate overall precision (S') using the
equation in Table 3, substituting X' for X; (3) calculate the range for
recovery at the spike concentration as (100 X'/T) 2.44 (100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4. If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Sections 8.2.1 or 8.3.2) to 1 L of reagent water.
The QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
2. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If P=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment for each parameter
on a regular basis (e.g. after each five to ten new accuracy
measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. When doubt exists over the
identification of a peak on the chromatogram, confirmatory techniques
such as gas chromatography with a dissimilar column, specific element
detector, or mass spectrometer must be used. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevent performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \8\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction.
9.3 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
[[Page 204]]
10.2 Add 60 mL of methylele chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2 min
with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the volume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.3 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.4 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.5 Pour the combined extract through a solvent-rinsed drying
column containing about 10 cm of anhydrous sodium sulfate, and collect
the extract in the K-D concentrator. Rinse the Erlenmeyer flask and
column with 20 to 30 mL of methylene chloride to complete the
quantitative transfer.
10.6 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 to 2 mL, remove the K-D apparatus and allow it to
drain and cool for at least 10 min.
Note: The dichloribenzenes have a sufficiently high volatility that
significant losses may occur in concentration steps if care is not
exercised. It is important to maintain a constant gentle evaporation
rate and not to allow the liquid volume to fall below 1 to 2 mL before
removing the K-D apparatus from the hot water bath.
10.7 Momentarily remove the Snyder column, add 50 mL of hexane and a
new boiling chip, and reattach the Snyder column. Raise the tempeature
of the water bath to 85 to 90 [deg]C. Concentrate the extract as in
Section 10.6, except use hexane to prewet the column. The elapsed time
of concentration should be 5 to 10 min.
10.8 Romove the Snyder column and rinse the flask and its lower
joint into the concentrator tube with 1 to 2 mL of hexane. A 5-mL
syringe is recommended for this operation. Stopper the concentrator tube
and store refrigerated if further processing will not be performed
immediately. If the extract will be stored longer than two days, it
should be transferred to a Teflon-sealed screw-cap vial. If the sample
extract requires no further cleanup, proceed with gas chromatographic
analysis (Section 12). If the sample requires further cleanup, proceed
to Section 11.
10.9 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use the procedure below or any other
appropriate procedure. However, the analyst first must demonstrate that
the requirements of Section 8.2 can be met using the method as revised
to incorporate the cleanup procedure.
11.2 Florisil column cleanup for chlorinated hydrocarbons:
11.2.1 Adjust the sample extract to 10 mL with hexane.
11.2.2 Place 12 g of Florisil into a chromatographic column. Tap the
column to settle the Florisil and add 1 to 2 cm of anhydrous sodium
sulfate to the top.
11.2.3 Preelute the column with 100 mL of petroleum ether. Discard
the eluate and just prior to exposure of the sodium sulfate layer to the
air, quantitatively transfer the sample extract onto the column by
decantation and subsequent petroleum ether washings. Discard the eluate.
Just prior to exposure of the sodium sulfate layer to the air, begin
eluting the column with 200 mL of petroleum ether and collect the eluate
in a 500-mL K-D flask equipped with a 10-mL concentrator tube. This
fraction should contain all of the chlorinated hydrocarbons.
11.2.4 Concentrate the fraction as in Section 10.6, except use
hexane to prewet the column. When the apparatus is cool, remove the
Snyder column and rinse the flask and its lower joint into the
concentrator tube with hexane. Analyze by gas chromatography (Section
12).
[[Page 205]]
12. Gas Chromatography
12.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Examples of the separations
achieved by Columl 2 are shown in Figures 1 and 2. Other packed or
capillary (open-tubular) columns, chromatographic conditions, or
detectors may be used if the requirements of Section 8.2 are met.
12.2 Calibrate the system daily as described in Section 7.
12.3 If the internal standard calibration procedure is being used,
the internal standard must be added to the sample extract and mixed
throughly immediately before injection into the gas chromatograph.
12.4 Inject 2 to 5 [micro]L of the sample extract or standard into
the gas chromatograph using the solvent-flush techlique. \9\ Smaller
(1.0 [micro]L) volumes may be injected if automatic devices are
employed. Record the volume injected to the nearest 0.05 [micro]L, the
total extract volume, and the resulting peak size in area or peak height
units.
12.5 Identify the parameters in the sample by comparing the
retention times of the peaks in the sample chromatogram with those of
the peaks in standard chromatograms. The width of the retention time
window used to make identifications should be based upon measurements of
actual retention time variations of standards over the course of a day.
Three times the standard deviation of a retention time for a compound
can be used to calculate a suggested window size; however, the
experience of the analyst should weigh heavily in the interpretation of
chromatograms.
12.6 If the response for a peak exceeds the working range of the
system, dilute the extract and reanalyze.
12.7 If the measurement of the peak response is prevented by the
presence of interferences, further cleanup is required.
13. Calculations
13.1 Determine the concentration of individual compounds in the
sample.
13.1.1 If the external standard calibration procedure is used,
calculate the amount of material injected from the peak response using
the calibration curve or calibration factor determined in Section 7.2.2.
The concentration in the sample can be calculated from Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.120
Equation 2
where:
A=Amount of material injected (ng).
Vi=Volume of extract injected ([micro]L).
Vt=Volume of total extract ([micro]L).
Vs=Volume of water extracted (mL).
13.1.2 If the internal standard calibration procedure is used,
calculate the concentration in the sample using the response factor (RF)
determined in Section 7.3.2 and Equation 3.
[GRAPHIC] [TIFF OMITTED] TC15NO91.121
Equation 3
where:
As=Response for the parameter to be measured.
Ais=Response for the internal standard.
Is=Amount of internal standard added to each extract
([micro]g).
Vo=Volume of water extracted (L).
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \10\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method has been tested for linearity of spike recovery
from reagent water and has been demonstrated to be applicable over the
concentration range from 4xMDL to 1000xMDL. \10\
14.3 This method was tested by 20 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 1.0 to 356 [micro]g/L. \11\ Single
operator precision, overall precision, and method accuracy were found to
be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of Chlorinated Hydrocarbons In Industrial and
Municipal Wastewaters, ``EPA 6090/4-84-ABC, National Technical
Information Service, PBXYZ, Springfield, Virginia, 22161 November 1984.
3. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American
[[Page 206]]
Society for Testing and Materials, Philadelphia.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,''American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
8. ASTM Annual Book of Standards, Part 31, D3370-76. ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
9. Burke, J.A. ``Gas Chromatography for Pesticide Residue Analysis;
Some Practical Aspects,'' Journal of the Association of Official
Analytical Chemists, 48, 1037 (1965).
10. ``Development of Detection Limits, EPA Method 612, Chlorinated
Hydrocarbons,'' Special letter report for EPA Contract 68-03-2625, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268.
11. ``EPA Method Study Method 612--Chlorinated Hydrocarbons,'' EPA
600/4-84-039, National Technical Information Service, PB84-187772,
Springfield, Virginia 22161, May 1984.
12. ``Method Performance for Hexachlorocyclopentadiene by Method
612,'' Memorandum from R. Slater, U.S. Environmental Protection Agency,
Environmental Monitoring and Support Laboratory, Cincinnati, Ohio 45268,
December 7, 1983.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Retention time (min) Method
-------------------------- detection
Parameter limit
Column 1 Column 2 ([micro]g/
L)
------------------------------------------------------------------------
1,3-Dichlorobenzene.............. 4.5 6.8 1.19
Hexachloroethane................. 4.9 8.3 0.03
1,4-Dichlorobenzene.............. 5.2 7.6 1.34
1,2-Dichlorobenzene.............. 6.6 9.3 1.14
Hexachlorobutadiene.............. 7.7 20.0 0.34
1,2,4-Trichlorobenzene........... 15.5 22.3 0.05
Hexachlorocyclopentadiene........ nd \c\ 16.5 0.40
2-Chloronaphthalene.............. \a\ 2.7 \b\ 3.6 0.94
Hexachlorobenzene................ \a\ 5.6 \b\ 10.1 0.05
------------------------------------------------------------------------
Column 1 conditions: Supelcoport (100/120 mesh) coated with 1% SP-1000
packed in a 1.8 m x 2 mm ID glass column with 5% methane/95% argon
carrier gas at 25 mL/min. flow rate. Column temperature held
isothermal at 65 [deg]C, except where otherwise indicated.
Column 2 conditions: Supelcoport (80/100 mesh) coated with 1.5% OV-1/
2.4% OV-225 packed in a 1.8 m x 2 mm ID glass column with 5% methane/
95% argon carrier gas at 25 mL/min. flow rate. Column temperature held
isothermal at 75 [deg]C, except where otherwise indicated.
nd=Not determined.
\a\ 150 [deg]C column temperature.
\b\ 165 [deg]C column temperature.
\c\ 100 [deg]C column temperature.
Table 2--QC Acceptance Criteria--Method 612
----------------------------------------------------------------------------------------------------------------
Limit for Range for X
Test conc. s ([micro]g/ Range for
Parameter ([micro]g/ ([micro]g/ L) P, Ps
L) L) (percent)
----------------------------------------------------------------------------------------------------------------
2-Chloronaphthalene............................................. 100 37.3 29.5-126.9 9-148
1,2-Dichlorobenzene............................................. 100 28.3 23.5-145.1 9-160
1,3-Dichlorobenzene............................................. 100 26.4 7.2-138.6 D-150
1,4-Dichlorobenzene............................................. 100 20.8 22.7-126.9 13-137
Hexachlorobenzene............................................... 10 2.4 2.6-14.8 15-159
Hexachlorobutadiene............................................. 10 2.2 D-12.7 D-139
Hexachlorocyclopentadiene....................................... 10 2.5 D-10.4 D-111
Hexachloroethane................................................ 10 3.3 2.4-12.3 8-139
1,2,4-Trichlorobenzene.......................................... 100 31.6 20.2-133.7 5-149
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
D=Detected; result must be greater than zero.
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
[[Page 207]]
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 612
----------------------------------------------------------------------------------------------------------------
Single analyst
Parameter Acccuracy, as recovery, precision, sr' Overall precision, S'
X' ([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
2-Chloronaphthalene................... 0.75C+3.21 0.28X-1.17 0.38X-1.39
1,2-Dichlorobenzene................... 0.85C-0.70 0.22X-2.95 0.41X-3.92
1,3-Dichlorobenzene................... 0.72C+0.87 0.21X-1.03 0.49X-3.98
1,4-Dichlorobenzene................... 0.72C+2.80 0.16X-0.48 0.35X-0.57
Hexachlorobenzene..................... 0.87C-0.02 0.14X+0.07 0.36X-0.19
Hexachlorobutadiene................... 0.61C+0.03 0.18X+0.08 0.53X-0.12
Hexachlorocyclopentadiene \a\......... 0.47C 0.24X 0.50X
Hexachloroethane...................... 0.74C-0.02 0.23X+0.07 0.36X-0.00
1,2,4-Trichlorobenzene................ 0.76C+0.98 0.23X-0.44 0.40X-1.37
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
\a\ Estimates based upon the performance in a single laboratory. \12\
[[Page 208]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.036
[[Page 209]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.037
[[Page 210]]
Method 613--2,3,7,8-Tetrachlorodibenzo-p-Dioxin
1. Scope and Application
1.1 This method covers the determination of 2,3,7,8-
tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD). The following parameter may
be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. GAS No.
------------------------------------------------------------------------
2,3,7,8-TCDD..................................... 34675 1746-01-6
------------------------------------------------------------------------
1.2 This is a gas chromatographic/mass spectrometer (GC/MS) method
applicable to the determination of 2,3,7,8-TCDD in municipal and
industrial discharges as provided under 40 CFR 136.1. Method 625 may be
used to screen samples for 2,3,7,8-TCDD. When the screening test is
positive, the final qualitative confirmation and quantification must be
made using Method 613.
1.3 The method detection limit (MDL, defined in Section 14.1) \1\
for 2,3,7,8-TCDD is listed in Table 1. The MDL for a specific wastewater
may be different from that listed, depending upon the nature of
interferences in the sample matrix.
1.4 Because of the extreme toxicity of this compound, the analyst
must prevent exposure to himself, of to others, by materials knows or
believed to contain 2,3,7,8-TCDD. Section 4 of this method contains
guidelines and protocols that serve as minimum safe-handling standards
in a limited-access laboratory.
1.5 Any modification of this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph/mass spectrometer
and in the interpretation of mass spectra. Each analyst must demonstrate
the ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is spiked with
an internal standard of labeled 2,3,7,8-TCDD and extracted with
methylene chloride using a separatory funnel. The methylene chloride
extract is exchanged to hexane during concentration to a volume of 1.0
mL or less. The extract is then analyzed by capillary column GC/MS to
separate and measure 2,3,7,8-TCDD. \2,3\
2.2 The method provides selected column chromatographic cleanup
proceudres to aid in the elimination of interferences that may be
encountered.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated backgrounds at the masses (m/z)
monitored. All of these materials must be routinely demonstrated to be
free from interferences under the conditions of the analysis by running
laboratory reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \4\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by the treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thorough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to
mininmize interference problems. Purification of solvents by
distillation in all-glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are
coextracted from the sample. The extent of matrix interferences will
vary considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled.
2,3,7,8-TCDD is often associated with other interfering chlorinated
compounds which are at concentrations several magnitudes higher than
that of 2,3,7,8-TCDD. The cleanup producers in Section 11 can be used to
overcome many of these interferences, but unique samples may require
additional cleanup approaches \1,5-7\ to eliminate false positives and
achieve the MDL listed in Table 1.
3.3 The primary column, SP-2330 or equivalent, resolves 2,3,7,8-TCDD
from the other 21 TCDD insomers. Positive results using any other gas
chromatographic column must be confirmed using the primary column.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to
[[Page 211]]
the lowest possible level by whatever means available. The laboratory is
responsible for maintaining a current awareness file of OSHA regulations
regarding the safe handling of the chemicals specified in this method. A
reference file of material data handling sheets should also be made
available to all personnel involved in the chemical analysis. Additional
references to laboratory safety are available and have been identified
8-10 for the information of the analyst. Benzene and 2,3,7,8-
TCDD have been identified as suspected human or mammalian carcinogens.
4.2 Each laboratory must develop a strict safety program for
handling 2,3,7,8-TCDD. The following laboratory practices are
recommended:
4.2.1 Contamination of the laboratory will be minimized by
conducting all manipulations in a hood.
4.2.2 The effluents of sample splitters for the gas chromatograph
and roughing pumps on the GC/MS should pass through either a column of
activated charcoal or be bubbled through a trap containing oil or high-
boiling alcohols.
4.2.3 Liquid waste should be dissolved in methanol or ethanol and
irradiated with ultraviolet light with a wavelength greater than 290 nm
for several days. (Use F 40 BL lamps or equivalent). Analyze liquid
wastes and dispose of the solutions when 2,3,7,8-TCDD can no longer be
detected.
4.3 Dow Chemical U.S.A. has issued the following precautimns
(revised November 1978) for safe handling of 2,3,7,8-TCDD in the
laboratory:
4.3.1 The following statements on safe handling are as complete as
possible on the basis of available toxicological information. The
precautions for safe handling and use are necessarily general in nature
since detailed, specific recommendations can be made only for the
particular exposure and circumstances of each individual use. Inquiries
about specific operations or uses may be addressed to the Dow Chemical
Company. Assistance in evaluating the health hazards of particular plant
conditions may be obtained from certain consulting laboratories and from
State Departments of Health or of Labor, many of which have an
industrial health service. 2,3,7,8-TCDD is extremely toxic to laboratory
animals. However, it has been handled for years without injury in
analytical and biological laboratories. Techniques used in handling
radioactive and infectious materials are applicable to 2,3,7,8,-TCDD.
4.3.1.1 Protective equipment--Throw-away plastic gloves, apron or
lab coat, safety glasses, and a lab hood adequate for radioactive work.
4.3.1.2 Training--Workers must be trained in the proper method of
removing contaminated gloves and clothing without contacting the
exterior surfaces.
4.3.1.3 Personal hygiene--Thorough washing of hands and forearms
after each manipulation and before breaks (coffee, lunch, and shift).
4.3.1.4 Confinement--Isolated work area, posted with signs,
segregated glassware and tools, plastic-backed absorbent paper on
benchtops.
4.3.1.5 Waste--Good technique includes minimizing contaminated
waste. Plastic bag liners should be used in waste cans. Janitors must be
trained in the safe handling of waste.
4.3.1.6 Disposal of wastes--2,3,7,8-TCDD decomposes above 800
[deg]C. Low-level waste such as absorbent paper, tissues, animal
remains, and plastic gloves may be burned in a good incinerator. Gross
quantities (milligrams) should be packaged securely and disposed through
commercial or governmental channels which are capable of handling high-
level radioactive wastes or extremely toxic wastes. Liquids should be
allowed to evaporate in a good hood and in a disposable container.
Residues may then be handled as above.
4.3.1.7 Decontamination--For personal decontamination, use any mild
soap with plenty of scrubbing action. For decontamination of glassware,
tools, and surfaces, Chlorothene NU Solvent (Trademark of the Dow
Chemical Company) is the least toxic solvent shown to be effective.
Satisfactory cleaning may be accomplished by rinsing with Chlorothene,
then washing with any detergent and water. Dishwater may be disposed to
the sewer. It is prudent to minimize solvent wastes because they may
require special disposal through commercial sources which are expensive.
4.3.1.8 Laundry--Clothing known to be contaminated should be
disposed with the precautions described under Section 4.3.1.6. Lab coats
or other clothing worn in 2,3,7,8-TCDD work areas may be laundered.
Clothing should be collected in plastic bags. Persons who convey the
bags and launder the clothing should be advised of the hazard and
trained in proper handling. The clothing may be put into a washer
without contact if the launderer knows the problem. The washer should be
run through a cycle before being used again for other clothing.
4.3.1.9 Wipe tests--A useful method of determining cleanliness of
work surfaces and tools is to wipe the surface with a piece of filter
paper. Extraction and analysis by gas chromatography can achieve a limit
of sensitivity of 0.1 [micro]g per wipe. Less than 1 [micro]g of
2,3,7,8-TCDD per sample indicates acceptable cleanliness; anything
higher warrants further cleaning. More than 10 [micro]g on a wipe sample
constitutes an acute hazard and requires prompt cleaning before further
use of the equipment or work space. A high (10 [micro]g)
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2,3,7,8-TCDD level indicates that unacceptable work practices have been
employed in the past.
4.3.1.10 Inhalation--Any procedure that may produce airborne
contamination must be done with good ventilation. Gross losses to a
ventilation system must not be allowed. Handling of the dilute solutions
normally used in analytical and animal work presents no inhalation
hazards except in the case of an accident.
4.3.1.11 Accidents--Remove contaminated clothing immediately, taking
precautions not to contaminate skin or other articles. Wash exposed skin
vigorously and repeatedly until medical attention is obtained.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composite sampling.
5.1.1 Grab sample bottle--1-L or 1-qt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. Before use, however, the compressible tubing should
be thoroughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.1.3 Clearly label all samples as ``POISON'' and ship according to
U.S. Department of Transportation regulations.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnels--2-L and 125-mL, with Teflon stopcock.
5.2.2 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.3 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-570001-
0500 or equivalent). Attach to concentrator tube with springs.
5.2.4 Snyder column, Kuderna-Danish--Three-ball macro (Kontes K-
503000-0121 or equivalent).
5.2.5 Snyder column, Kuderna-Danish--Two-ball micro (Kontes K-
569001-0219 or equivalent).
5.2.6 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.7 Chromatographic column--300 mm long x 10 mm ID, with Teflon
stopcock and coarse frit filter disc at bottom.
5.2.8 Chromatographic column--400 mm long x 11 mm ID, with Teflon
stopcock and coarse frit filter disc at bottom.
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min or Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2 [deg]C). The bath should be
used in a hood.
5.5 GC/MS system:
5.5.1 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph and all required accessories
including syringes, analytical columns, and gases. The injection port
must be designed for capillary columns. Either split, splitless, or on-
column injection techniques may be employed, as long as the requirements
of Section 7.1.1 are achieved.
5.5.2 Column--60 m long x 0.25 mm ID glass or fused silica, coated
with SP-2330 (or equivalent) with a film thickness of 0.2 [micro]m. Any
equivalent column must resolve 2, 3, 7, 8-TCDD from the other 21 TCDD
isomers. \16\
5.5.3 Mass spectrometer--Either a low resolution mass spectrometer
(LRMS) or a high resolution mass spectrometer (HRMS) may be used. The
mass spectrometer must be equipped with a 70 V (nominal) ion source and
be capable of aquiring m/z abundance data in real time selected ion
monitoring (SIM) for groups of four or more masses.
5.5.4 GC/MS interface--Any GC to MS interface can be used that
achieves the requirements of Section 7.1.1. GC to MS interfaces
constructed of all glass or glass-lined materials are recommended. Glass
surfaces can be deactivated by silanizing with dichlorodimethylsilane.
To achieve maximum sensitivity, the exit end of the capillary column
should be placed in the ion source. A short piece of fused silica
capillary can be used as the interface to overcome problems associated
with straightening the exit end of glass capillary columns.
5.5.5 The SIM data acquired during the chromatographic program is
defined as the Selected Ion Current Profile (SICP). The SICP can be
acquired under computer control or as a real time analog output. If
computer control is used, there must be software available to plot the
SICP and report peak height or area data for any m/z in the SICP between
specified time or scan number limits.
5.6 Balance--Analytical, capable of accurately weighing 0.0001 g.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of 2, 3, 7, 8-TCDD.
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6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL. Wash the solution with methylene
chloride and hexane before use.
6.3 Sodium thiosulfate--(ACS) Granular.
6.4 Sulfuric acid--Concentrated (ACS, sp. gr. 1.84).
6.5 Acetone, methylene chloride, hexane, benzene, ortho-xylene,
tetradecane--Pesticide quality or equivalent.
6.6 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.7 Alumina--Neutral, 80/200 mesh (Fisher Scientific Co., No. A-540
or equivalent). Before use, activate for 24 h at 130 [deg]C in a foil-
covered glass container.
6.8 Silica gel--High purity grade, 100/120 mesh (Fisher Scientific
Co., No. S-679 or equivalent).
6.9 Stock standard solutions (1.00 [micro]g/[micro]L)--Stock
standard solutimns can be prepared from pure standard materials or
purchased as certified solutions. Acetone should be used as the solvent
for spiking solutions; ortho-xylene is recommended for calibration
standards for split injectors; and tetradecane is recommended for
splitless or on-colum injectors. Analyze stock internal standards to
verify the absence of native 2,3,7,8-TCDD.
6.9.1 Prepare stock standard solutions of 2,3,7,8-TCDD (mol wt 320)
and either \37\C14 2,3,7,8-TCDD (mol wt 328) or
\13\C112 2,3,7,8-TCDD (mol wt 332) in an isolated area by
accurately weighing about 0.0100 g of pure material. Dissolve the
material in pesticide quality solvent and dilute to volume in a 10-mL
volumetric flask. When compound purity is assayed to be 96% or greater,
the weight can be used without correction to calculate the concentration
of the stock standard. Commercially prepared stock standards can be used
at any concentration if they are certified by the manufacturer or by an
independent source.
6.9.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store in an isolated refrigerator protected from
light. Stock standard solutions should be checked frequently for signs
of degradation or evaporation, especially just prior to preparing
calibration standards or spiking solutions from them.
6.9.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with check standards indicates a problem.
6.10 Internal standard spiking solution (25 ng/mL)--Using stock
standard solution, prepare a spiking solution in acetone of either \13\
Cl12 or \37\ Cl4 2,3,7,8-TCDD at a concentration
of 25 ng/mL. (See Section 10.2)
6.11 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatograhic operating conditions equivalent to
those given in Table 1 and SIM conditions for the mass spectrometer as
described in Section 12.2 The GC/MS system must be calibrated using the
internal standard technique.
7.1.1 Using stock standards, prepare calibration standards that will
allow measurement of relative response factors of at least three
concentration ratios of 2,3,7,8-TCDD to internal standard. Each
calibration standard must be prepared to contain the internal standard
at a concentration of 25 ng/mL. If any interferences are contributed by
the internal standard at m/z 320 and 322, its concentration may be
reduced in the calibration standards and in the internal standard
spiking solution (Section 6.10). One of the calibration standards should
contain 2,3,7,8-TCDD at a concentration near, but above, the MDL and the
other 2,3,7,8-TCDD concentrations should correspond to the expected
range of concentrations found in real samples or should define the
working range of the GC/MS system.
7.1.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standardaccording to Section 12 and tabulate peak height or area
response against the concentration of 2,3,7,8-TCDD and internal
standard. Calculate response factors (RF) for 2,3,7,8-TCDD using
Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.122
Equation 1
where:
As=SIM response for 2,3,7,8-TCDD m/z 320.
Ais=SIM response for the internal standard, m/z 332 for \13\
C12 2,3,7,8-TCDD m/z 328 for \37\ Cl4 2,3,7,8-
TCDD.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of 2,3,7,8-TCDD ([micro]g/L).
If the RF value over the working range is a constant (<10% relative
standard deviation, RSD), the RF can be assumed to be invariant and the
average RF can be used for calculations. Alternatively, the results can
be used to plot a calibration curve of response ratios, As/
Ais, vs. RF.
7.1.3 The working calibration curve or RF must be verified on each
working day by the measurement of one or more 2,3,7,8-TCDD calibration
standards. If the response for 2,3,7,8-TCDD varies from the predicted
response by more than 15%, the test must be
repeated using a fresh calibration standard. Alternatively, a new
calibration curve must be prepared.
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7.2 Before using any cleanup procedure, the analyst must process a
series of calibration standards through the procedure to validate
elution patterns and the absence of interferences from the reagents.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.5, 11.1, and 12.1) to improve the separations or lower the
cost of measurements. Each time such a modification is made to the
method, the analyst is required to repeat the procedure in Section 8.2
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 10% of all samples with native 2,3,7,8-TCDD to monitor and
evaluate laboratory data quality. This procedure is described in Section
8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 10% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing 2,3,7,8-TCDD at a concentration of 0.100 [micro]g/mL in
acetone. The QC check sample concentrate must be obtained from the U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory in Cincinnati, Ohio, if available. If not available from that
source, the QC check sample concentrate must be obtained from another
external source. If not available from either source above, the QC check
sample concentrate must be prepared by the laboratory using stock
standards prepared independently from those used for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
0.100 [micro]g/L (100 ng/L) by adding 1.00 mL of QC check sample
concentrate to each of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for 2,3,7,8-TCDD
using the four results.
8.2.5 Compare s and (X) with the corresponding acceptance criteria
for precision and accuracy, respectively, found in Table 2. If s and X
meet the acceptance criteria, the system performance is acceptable and
analysis of actual samples can begin. If s exceeds the precision limit
or X falls outside the range for accuracy, the system performance is
unacceptable for 2,3,7,8-TCDD. Locate and correct the source of the
problem and repeat the test beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 10% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing one to ten samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of
2,3,7,8-TCDD in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of 2,3,7,8-TCDD in the sample is not
being checked against a limit specific to that parameter, the spike
should be at 0.100 [micro]g/L or 1 to 5 times higher than the background
concentration determined in Section 8.3.2, whichever concentration would
be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the
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spike concentration should be (1) the regulatory concentration limit, if
any; or, if none (2) the larger of either 5 times higher than the
expected background concentration or 0.100 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of 2,3,7,8-TCDD. If necessary, prepare a new QC check
sample concentrate (Section 8.2.1) appropriate for the background
concentration in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of 2,3,7,8-TCDD. Calculate percent
recovery (P) as 100(A-B)%T, where T is the known true value of the
spike.
8.3.3 Compare the percent recovery (P) for 2,3,7,8-TCDD with the
corresponding QC acceptance criteria found in Table 2. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\11\ If spiking was performed at a concentration lower than 0.100
[micro]g/L, the analyst must use either the QC acceptance criteria in
Table 2, or optional QC acceptance criteria calculated for the specific
spike concentration. To calculate optional acceptance criteria for the
recovery of 2,3,7,8-TCDD: (1) Calculate accuracy (X') using the equation
in Table 3, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 3,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T)2.44(100 S'/T)%. \11\
8.3.4 If the recovery of 2,3,7,8-TCDD falls outside the designated
range for recovery, a check standard must be analyzed as described in
Section 8.4.
8.4 If the recovery of 2,3,7,8-TCDD fails the acceptance criteria
for recovery in Section 8.3, a QC check standard must be prepared and
analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the complexity of the sample matrix and the performance
of the laboratory.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of 2,3,7,8-TCDD. Calculate the percent recovery
(Ps) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) with the
corresponding QC acceptance criteria found in Table 2. If the recovery
of 2,3,7,8-TCDD falls outside the designated range, the laboratory
performance is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for 2,3,7,8-
TCDD in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the spandard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P-2sp to P+2sp.
If P=90% and sp=10%, for example, the accuracy interval is
expressed as 70-110%. Update the accuracy assessment on a regular basis
(e.g. after each five to ten new accuracy measurements).
8.6 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \12\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All samples must be iced or refrigerated at 4 [deg]C and
protected from light from the time of collection until extraction. Fill
the sample bottles and, if residual chlorine is present, add 80 mg of
sodium thiosulfate per liter of sample and mix well. EPA Methods 330.4
and 330.5 may be used for measurement of residual chlorine. \13\ Field
test kits are available for this purpose.
9.3 Label all samples and containers ``POISON'' and ship according
to applicable U.S. Department of Transportation regulations.
9.4 All samples must be extracted within 7 days of collection and
completely analyzed within 40 days of extraction. \2\
10. Sample Extraction
Caution: When using this method to analyze for 2,3,7,8-TCDD, all of
the following operations must be performed in a limited-access
laboratory with the analyst wearing full
[[Page 216]]
protective covering for all exposed skin surfaces. See Section 4.2.
10.1 Mark the water meniscus on the side of the sample bottle for
later determination of sample volume. Pour the entire sample into a 2-L
separatory funnel.
10.2 Add 1.00 mL of internal standard spiking solution to the sample
in the separatory funnel. If the final extract will be concentrated to a
fixed volume below 1.00 mL (Section 12.3), only that volume of spiking
solution should be added to the sample so that the final extract will
contain 25 ng/mL of internal standard at the time of analysis.
10.3 Add 60 mL of methylene chloride to the sample bottle, seal, and
shake 30 s to rinse the inner surface. Transfer the solvent to the
separatory funnel and extract the sample by shaking the funnel for 2
min. with periodic venting to release excess pressure. Allow the organic
layer to separate from the water phase for a minimum of 10 min. If the
emulsion interface between layers is more than one-third the vmlume of
the solvent layer, the analyst must employ mechanical techniques to
complete the phase separation. The optimum technique depends upon the
sample, but may include stirring, filtration of the emulsion through
glass wool, centrifugation, or other physical methods. Collect the
methylene chloride extract in a 250-mL Erlenmeyer flask.
10.4 Add a second 60-mL volume of methylene chloride to the sample
bottle and repeat the extraction procedure a second time, combining the
extracts in the Erlenmeyer flask. Perform a third extraction in the same
manner.
10.5 Assemble a Kuderna-Danish (K-D) concentrator by attaching a 10-
mL concentrator tube to a 500-mL evaporative flask. Other concentration
devices or techniques may be used in place of the K-D concentrator if
the requirements of Section 8.2 are met.
10.6 Pour the combined extract into the K-D concentrator. Rinse the
Erlenmeyer flask with 20 to 30 mL of methylele chloride to complete the
quantitative transfer.
10.7 Add one or two clean boiling chips to the evaporative flask and
attach a three-ball Snyder column. Prewet the Snyder column by adding
about 1 mL of methylene chloride to the top. Place the K-D apparatus on
a hot water bath (60 to 65 [deg]C) so that the concentrator tube is
partially immersed in the hot water, and the entire lower rounded
surface of the flask is bathed with hot vapor. Adjust the vertical
position of the apparatus and the water temperature as required to
complete the concentration in 15 to 20 min. At the proper rate of
distillation the balls of the column will actively chatter but the
chambers will not flood with condensed solvent. When the apparent volume
of liquid reaches 1 mL, remove the K-D apparatus and allow it to drain
and cool for at least 10 min.
10.8 Momentarily remove the Snyder column, add 50 mL of hexane and a
new boiling chip, and reattach the Snyder column. Raise the temperature
of the water bath to 85 to 90[deg]C. Concentrate the extract as in
Section 10.7, except use hexane to prewet the column. Remove the Snyder
column and rinse the flask and its lower joint into the concentrator
tube with 1 to 2 mL of hexane. A 5-mL syringe is recommended for this
operation. Set aside the K-D glassware for reuse in Section 10.14.
10.9 Pour the hexane extract from the concentrator tube into a 125-
mL separatory funnel. Rinse the concentrator tube four times with 10-mL
aliquots of hexane. Combine all rinses in the 125-mL separatory funnel.
10.10 Add 50 mL of sodium hydroxide solution to the funnel and shake
for 30 to 60 s. Discard the aqueous phase.
10.11 Perform a second wash of the organic layer with 50 mL of
reagent water. Discard the aqueous phase.
10.12 Wash the hexane layer with a least two 50-mL aliquots of
concentrated sulfuric acid. Continue washing the hexane layer with 50-mL
aliquots of concentrated sulfuric acid until the acid layer remains
colorless. Discard all acid fractions.
10.13 Wash the hexane layer with two 50-mL aliquots of reagent
water. Discard the aqueous phases.
10.14 Transfer the hexane extract into a 125-mL Erlenmeyer flask
containing 1 to 2 g of anhydrous sodium sulfate. Swirl the flask for 30
s and decant the hexane extract into the reassembled K-D apparatus.
Complete the quantitative transfer with two 10-mL hexane rinses of the
Erlenmeyer flask.
10.15 Replace the one or two clean boiling chips and concentrate the
extract to 6 to 10 mL as in Section 10.8.
10.16 Add a clean boiling chip to the concentrator tube and attach a
two-ball micro-Snyder column. Prewet the column by adding about 1 mL of
hexane to the top. Place the micro-K-D apparatus on the water bath so
that the concentrator tube is partially immersed in the hot water.
Adjust the vertical position of the apparatus and the water temperature
as required to complete the concentration in 5 to 10 min. At the proper
rate of distillation the balls of the column will actively chatter but
the chambers will not flood. When the apparent volume of liquid reaches
about 0.5 mL, remove the K-D apparatus and allow it to drain and cool
for at least 10 min. Remove the micro-Snyder column and rinse its lower
joint into the concentrator tube with 0.2 mL of hexane.
Adjust the extract volume to 1.0 mL with hexane. Stopper the
concentrator tube and store refrigerated and protected from light if
further processing will not be performed immediately. If the extract
will be stored
[[Page 217]]
longer than two days, it should be transferred to a Teflon-sealed screw-
cap vial. If the sample extract requires no further cleanup, proceed
with GC/MS analysis (Section 12). If the sample requires further
cleanup, proceed to Section 11.
10.17 Determine the original sample volume by refilling the sample
bottle to the mark and transferring the liquid to a 1000-mL graduated
cylinder. Record the sample volume to the nearest 5 mL.
11. Cleanup and Separation
11.1 Cleanup procedures may not be necessary for a relatively clean
sample matrix. If particular circumstances demand the use of a cleanup
procedure, the analyst may use either procedure below or any other
appropriate procedure. \1,5-7\ However, the analyst first must
demonstrate that the requirements of Section 8.2 can be met using the
method as revised to incorporate the cleanup procedure. Two cleanup
column options are offered to the analyst in this section. The alumina
column should be used first to overcome interferences. If background
problems are still encountered, the silica gel column may be helpful.
11.2 Alumina column cleanup for 2,3,7,8-TCDD:
11.2.1 Fill a 300 mm long x 10 mm ID chromatographic column with
activated alumina to the 150 mm level. Tap the column gently to settle
the alumina and add 10 mm of anhydrous sodium sulfate to the top.
11.2.2 Preelute the column with 50 mL of hexane. Adjust the elution
rate to 1 mL/min. Discard the eluate and just prior to exposure of the
sodium sulfate layer to the air, quantitatively transfer the 1.0-mL
sample extract onto the column using two 2-mL portions of hexane to
complete the transfer.
11.2.3 Just prior to exposure of the sodium sulfate layer to the
air, add 50 mL of 3% methylene chloride/95% hexane (V/V) and continue
the elution of the column. Discard the eluate.
11.2.4 Next, elute the column with 50 mL of 20% methylene chloride/
80% hexane (V/V) into a 500-mL K-D flask equipped with a 10-mL
concentrator tube. Concentrate the collected fraction to 1.0 mL as in
Section 10.16 and analyze by GC/MS (Section 12).
11.3 Silica gel column cleanup for 2,3,7,8-TCDD:
11.3.1 Fill a 400 mm long x 11 mm ID chromatmgraphic column with
silica gel to the 300 mm level. Tap the column gently to settle the
silica gel and add 10 mm of anhydrous sodium sulfate to the top.
11.3.2 Preelute the column with 50 mL of 20% benzene/80% hexane (V/
V). Adjust the elution rate to 1 mL/min. Discard the eluate and just
prior to exposure of the sodium sulfate layer to the air, quantitatively
transfer the 1.0-mL sample extract onto the column using two 2-mL
portions of 20% benzene/80% hexane to complete the transfer.
11.3.3 Just prior to exposure of the sodium sulfate layer to the
air, add 40 mL of 20% benzene/80% hexane to the column. Collect the
eluate in a clean 500-mL K-D flask equipped with a 10-mL concentrator
tube. Concentrate the collected fraction to 1.0 mL as in Section 10.16
and analyze by GC/MS.
12. GC/MS Analysis
12.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. Other capillary columns or
chromatographic conditions may be used if the requirements of Sections
5.5.2 and 8.2 are met.
12.2 Analyze standards and samples with the mass spectrometer
operating in the selected ion monitoring (SIM) mode using a dwell time
to give at least seven points per peak. For LRMS, use masses at m/z 320,
322, and 257 for 2,3,7,8-TCDD and either m/z 328 for \37\Cl4
2,3,7,8-TCDD or m/z 332 for \13\C12 2,3,7,8-TCDD. For HRMS,
use masses at m/z 319.8965 and 321.8936 for 2,3,7,8-TCDD and either m/z
327.8847 for \37\Cl4 2,3,7,8-TCDD or m/z 331.9367 for
\13\C12 2,3,7,8-TCDD.
12.3 If lower detection limits are required, the extract may be
carefully evaporated to dryness under a gentle stream of nitrogen with
the concentrator tube in a water bath at about 40 [deg]C. Conduct this
operation immediately before GC/MS analysis. Redissolve the extract in
the desired final volume of ortho-xylene or tetradecane.
12.4 Calibrate the system daily as described in Section 7.
12.5 Inject 2 to 5 [micro]L of the sample extract into the gas
chromatograph. The volume of calibration standard injected must be
measured, or be the same as all sample injection volumes.
12.6 The presence of 2,3,7,8-TCDD is qualitatively confirmed if all
of the following criteria are achieved:
12.6.1 The gas chromatographic column must resolve 2,3,7,8-TCDD from
the other 21 TCDD isomers.
12.6.2 The masses for native 2,3,7,8-TCDD (LRMS-m/z 320, 322, and
257 and HRMS-m/z 320 and 322) and labeled 2,3,7,8-TCDD (m/z 328 or 332)
must exhibit a simultaneous maximum at a retention time that matches
that of native 2,3,7,8-TCDD in the calibration standard, with the
performance specifications of the analytical system.
12.6.3 The chlorine isotope ratio at m/z 320 and m/z 322 must agree
to within10% of that in the calibration standard.
12.6.4 The signal of all peaks must be greater than 2.5 times the
noise level.
12.7 For quantitation, measure the response of the m/z 320 peak for
2,3,7,8-TCDD
[[Page 218]]
and the m/z 332 peak for \13\C12 2,3,7,8-TCDD or the m/z 328
peak for \37\Cl4 2,3,7,8-TCDD.
12.8 Co-eluting impurities are suspected if all criteria are
achieved except those in Section 12.6.3. In this case, another SIM
analysis using masses at m/z 257, 259, 320 and either m/a 328 or m/z 322
can be performed. The masses at m/z 257 and m/z 259 are indicative of
the loss of one chlorine and one carbonyl group from 2,3,7,8-TCDD. If
masses m/z 257 and m/z 259 give a chlorine isotope ratio that agrees to
within 10% of the same cluster in the calibration
standards, then the presence of TCDD can be confirmed. Co-eluting DDD,
DDE, and PCB residues can be confirmed, but will require another
injection using the appropriate SIM masses or full repetitive mass
scans. If the response for \37\Cl4 2,3,7,8-TCDD at m/z 328 is
too large, PCB contamination is suspected and can be confirmed by
examining the response at both m/z 326 and m/z 328. The
\37\Cl4 2,3,7,8-TCDD internal standard gives negligible
response at m/z 326. These pesticide residues can be removed using the
alumina column cleanup procedure.
12.9 If broad background interference restricts the sensitivity of
the GC/MS analysis, the analyst should employ additional cleanup
procedures and reanalyze by GC/MS.
12.10 In those circumstances where these procedures do not yield a
definitive conclusion, the use of high resolution mass spectrometry is
suggested. \5\
13. Calculations
13.1 Calculate the concentration of 2,3,7,8-TCDD in the sample using
the response factor (RF) determined in Section 7.1.2 and Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.123
Equation 2
where:
As=SIM response for 2,3,7,8-TCDD at m/z 320.
Ais=SIM response for the internal standard at m/z 328 or 332.
Is=Amount of internal standard added to each extract
([micro]g).
Vo=Volume of water extracted (L).
13.2 For each sample, calculate the percent recovery of the internal
standard by comparing the area of the m/z peak measured in the sample to
the area of the same peak in the calibration standard. If the recovery
is below 50%, the analyst should review all aspects of his analytical
technique.
13.3 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentration
listed in Table 1 was obtained using reagent water. \14\ The MDL
actually achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method was tested by 11 laboratories using reagent water,
drinking water, surface water, and three industrial wastewaters spiked
at six concentrations over the range 0.02 to 0.20 [micro]g/L. \15\
Single operator precision, overall precision, and method accuracy were
found to be directly related to the concentration of the parameter and
essentially independent of the sample matrix. Linear equations to
describe these relationships are presented in Table 3.
References
1. 40 CFR part 136, appendix B.
2. ``Determination of TCDD in Industrial and Municipal
Wastewaters,'' EPA 600/4-82-028, National Technical Information Service,
PB82-196882, Springfield, Virginia 22161, April 1982.
3. Buser, H.R., and Rappe, C. ``High Resolution Gas Chromatography
of the 22 Tetrachlorodibenzo-p-dioxin Isomers,'' Analytical Chemistry,
52, 2257 (1980).
4. ASTM Annual Book of Standards, Part 31, D3694-78. ``Standard
Practices for Preparation of Sample Containers and for Preservation of
Organic Constituents,'' American Society for Testing and Materials,
Philadelphia.
5. Harless, R. L., Oswald, E. O., and Wilkinson, M. K. ``Sample
Preparation and Gas Chromatography/Mass Spectrometry Determination of
2,3,7,8-Tetrachlorodibenzo-p-dioxin,'' Analytical Chemistry, 52, 1239
(1980).
6. Lamparski, L. L., and Nestrick, T. J. ``Determination of Tetra-,
Hepta-, and Octachlorodibenzo-p-dioxin Isomers in Particulate Samples at
Parts per Trillion Levels,'' Analytical Chemistry, 52, 2045 (1980).
7. Longhorst, M. L., and Shadoff, L. A. ``Determination of Parts-
per-Trillion Concentrations of Tetra-, Hexa-, and Octachlorodibenzo-p-
dioxins in Human Milk,'' Analytical Chemistry, 52, 2037 (1980).
8. ``Carcinogens--Working with Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
9. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occuptional Safety and Health Administration, OSHA 2206
(Revised, January 1976).
[[Page 219]]
10. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
11. Provost, L. P., and Elder, R. S., ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.3.3 is two times the value 1.22
derived in this report.)
12. ASTM Annual Book of Standards, Part 31, D3370-76, ``Standard
Practices for Sampling Water,'' American Society for Testing and
Materials, Philadelphia.
13. ``Methods, 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
14. Wong, A.S. et al. ``The Determination of 2,3,7,8-TCDD in
Industrial and Municipal Wastewaters, Method 613, Part 1--Development
and Detection Limits,'' G. Choudhay, L. Keith, and C. Ruppe, ed.,
Butterworth Inc., (1983).
15. ``EPA Method Study 26, Method 613: 2,3,7,8-Tetrachlorodibenzo-p-
dioxin,'' EPA 600/4-84-037, National Technical Information Service,
PB84-188879, Springfield, Virginia 22161, May 1984.
Table 1--Chromatographic Conditions and Method Detection Limit
------------------------------------------------------------------------
Method
Retention detection
Parameter time limit
(min) ([micro]g/
L)
------------------------------------------------------------------------
2,3,7,8-TCDD..................................... 13.1 0.002
------------------------------------------------------------------------
Column conditions: SP-2330 coated on a 60 m long x 0.25 mm ID glass
column with hydrogen carrier gas at 40 cm/sec linear velocity,
splitless injection using tetradecane. Column temperature held
isothermal at 200[deg]C for 1 min, then programmed at 8[deg]C/min to
250 [deg]C and held. Use of helium carrier gas will approximately
double the retention time.
Table 2--QC Acceptance Criteria--Method 613
----------------------------------------------------------------------------------------------------------------
Limit for
Test conc. s Range for X Range
Parameter ([micro]g/ ([micro]g/ ([micro]g/L) for P,
L) L) Ps (%)
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDD................................................... 0.100 0.0276 0.0523-0.1226 45-129
----------------------------------------------------------------------------------------------------------------
s=Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X=Average recovery for four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps=Percent recovery measured (Section 8.3.2, Section 8.4.2).
Note: These criteria are based directly upon the method performance data in Table 3. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 3.
Table 3--Method Accuracy and Precision as Functions of Concentration--Method 613
----------------------------------------------------------------------------------------------------------------
Accuracy, as Single analyst,
Parameter recovery, X ' precision, sr ' Overall precision,
([micro]g/L) ([micro]/L) S ' ([micro]/g/L)
----------------------------------------------------------------------------------------------------------------
2,3,7,8-TCDD........................................ 0.86C+0.00145 0.13X+0.00129 0.19X+0.00028
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements. of a sample containing a concentration of C, in [micro]g/L.
sr'=Expected single analyst standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found of X, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
Method 624--Purgeables
1. Scope and Application
1.1 This method covers the determination of a number of purgeable
organics. The following parameters may be determined by this method:
------------------------------------------------------------------------
STORET
Parameter No. CAS No.
------------------------------------------------------------------------
Benzene.......................................... 34030 71-43-2
Bromodichloromethane............................. 32101 75-27-4
Bromoform........................................ 32104 75-25-2
Bromomethane..................................... 34413 74-83-9
Carbon tetrachloride............................. 32102 56-23-5
Chlorobenzene.................................... 34301 108-90-7
Chloroethane..................................... 34311 75-00-3
2-Chloroethylvinyl ether......................... 34576 110-75-8
Chloroform....................................... 32106 67-66-3
Chloromethane.................................... 34418 74-87-3
Dibromochloromethane............................. 32105 124-48-1
1,2-Dichlorobenzene.............................. 34536 95-50-1
1,3-Dichlorobenzene.............................. 34566 541-73-1
1,4-Dichlorobenzene.............................. 34571 106-46-7
1,1-Dichloroethane............................... 34496 75-34-3
1,2-Dichloroethane............................... 34531 107-06-2
1,1-Dichloroethane............................... 34501 75-35-4
trans-1,2-Dichloroethene......................... 34546 156-60-5
1,2-Dichloropropane.............................. 34541 78-87-5
cis-1,3-Dichloropropene.......................... 34704 10061-01-5
trans-1,3-Dichloropropene........................ 34699 10061-02-6
Ethyl benzene.................................... 34371 100-41-4
Methylene chloride............................... 34423 75-09-2
1,1,2,2-Tetrachloroethane........................ 34516 79-34-5
Tetrachloroethene................................ 34475 127-18-4
Toluene.......................................... 34010 108-88-3
1,1,1-Trichloroethene............................ 34506 71-55-6
1,1,2-Trichloroethene............................ 34511 79-00-5
Trichloroethane.................................. 39180 79-01-6
Trichlorofluoromethane........................... 34488 75-69-4
Vinyl chloride................................... 39175 75-01-4
------------------------------------------------------------------------
[[Page 220]]
1.2 The method may be extended to screen samples for acrolein
(STORET No. 34210, CAS No. 107-02-8) and acrylonitrile (STORET No.
34215, CAS No. 107-13-1), however, the preferred method for these two
compounds in Method 603.
1.3 This is a purge and trap gas chromatographic/mass spectrometer
(GC/MS) method applicable to the determination of the compounds listed
above in municipal and industrial discharges as provided under 40 CFR
136.1.
1.4 The method detection limit (MDL, defined in Section 14.1) \1\
for each parameter is listed in Table 1. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.5 Any modification to this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5. Depending upon the nature of the modification and the extent
of intended use, the applicant may be required to demonstrate that the
modifications will produce equivalent results when applied to relevant
wastewaters.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the operation of a purge and trap system and a
gas chromatograph/mass spectrometer and in the interpretation of mass
spectra. Each analyst must demonstrate the ability to generate
acceptable results with this method using the procedure described in
Section 8.2.
2. Summary of Method
2.1 An inert gas is bubbled through a 5-mL water sample contained in
a specially-designed purging chamber at ambient temperature. The
purgeables are efficiently transferred from the aqueous phase to the
vapor phase. The vapor is swept through a sorbent trap where the
purgeables are trapped. After purging is completed, the trap is heated
and backflushed with the inert gas to desorb the purgeables onto a gas
chromatographic column. The gas chromatograph is temperature programmed
to separate the purgeables which are then detected with a mass
spectrometer. \2,3\
3. Interferences
3.1 Impurities in the purge gas, organic compounds outgassing from
the plumbing ahead of the trap, and solvent vapors in the laboratory
account for the majority of contamination problems. The analytical
system must be demonstated to be free from contamination under the
conditions of the analysis by running laboratory reagent blanks as
described in Section 8.1.3. The use of non-Teflon plastic tubing, non-
Teflon thread sealants, or flow controllers with rubber components in
the purge and trap system should be avoided.
3.2 Samples can be contaminated by diffusion of volatile organics
(particularly fluorocarbons and methylene chloride) through the septum
seal into the sample during shipment and storage. A field reagent blank
prepared from reagent water and carried through the sampling and
handling protocol can serve as a check on such contamination.
3.3 Contamination by carry-over can occur whenever high level and
low level samples are sequentially analyzed. To reduce carry-over, the
purging device and sample syringe must be rinsed with reagent water
between sample analyses. Whenever an unusually concentrated sample is
encountered, it should be followed by an analysis of reagent water to
check for cross contamination. For samples containing large amounts of
water-soluble materials, suspended solids, high boiling compounds or
high pureeable levels, it may be necessary to wash the purging device
with a detergent solution, rinse it with distilled water, and then dry
it in a 105 [deg]C oven between analyses. The trap and other parts of
the system are also subject to contamination; therefore, frequent
bakeout and purging of the entire system may be required.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method has not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this methmd. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified
4-6 for the information of the analyst.
4.2. The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: benzene, carbon tetrachloride, chloroform, 1,4-
dichlorobenzene, and vinyl chloride. Primary standards of these toxic
compounds should be prepared in a hood. A NIOSH/MESA approved toxic gas
respirator should be worn when the analyst handles high concentrations
of these toxic compounds.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete sampling.
[[Page 221]]
5.1.1 Vial--25-mL capacity or larger, equipped with a screw cap with
a hole in the center (Pierce 13075 or equivalent). Detergent
wash, rinse with tap and distilled water, and dry at 105 [deg]C before
use.
5.1.2 Septum--Teflon-faced silicane (Pierce 12722 or
equivalent). Detergent wash, rinse with tap and distilled water, and dry
at 105 [deg]C for 1 h before use.
5.2 Purge and trap system--The purge and trap system consists of
three separate pieces of equipment: A purging device, trap, and
desorber. Several complete systems are now commercially available.
5.2.1 The purging device must be designed to accept 5-mL samples
with a water column at least 3 cm deep. The gaseous head space between
the water column and the trap must have a total volume of less than 15
mL. The purge gas must pass though the water column as finely divided
bubbles with a diameter of less than 3 mm at the origin. The purge gas
must be introduced no more than 5 mm from the base of the water column.
The purging device illustrated in Figure 1 meets these design criteria.
5.2.2 The trap must be at least 25 cm long and have an inside
diameter of at least 0.105 in. The trap must be packed to contain the
following minimum lengths of adsorbents: 1.0 cm of methyl silicone
coated packing (Section 6.3.2), 15 cm of 2,6-dyphenylene oxide polymer
(Section 6.3.1), and 8 cm of silica gel (Section 6.3.3). The minimum
specifications for the trap are illustrated in Figure 2.
5.2.3 The desorber should be capable of rapidly heating the trap to
180 [deg]C. The polymer section of the trap should not be heated higher
than 180 [deg]C and the remaining sections should not exceed 200 [deg]C.
The desorber illustrated in Figure 2 meets these design criteria.
5.2.4 The purge and trap system may be assembled as a separate unit
or be coupled to a gas chromatograph as illustrated in Figures 3 and 4.
5.3 GC/MS system:
5.3.1 Gas chromatograph--An analytical system complete with a
temperature programmable gas chromatograph suitable for on-column
injection and all required accessories including syringes, analytical
columns, and gases.
5.3.2 Column--6 ft long x 0.1 in ID stainless steel or glass, packed
with 1% SP-1000 on Carbopack B (60/80 mesh) or equivalent. This column
was used to develop the method performance statements in Section 14.
Guidelines for the use of alternate column packings are provided in
Section 11.1.
5.3.3 Mass spectrometer--Capable of scanning from 20 to 260 amu
every 7 s or less, utilizing 70 V (nominal) electron energy in the
electron impact ionization mode, and producing a mass spectrum which
meets all the criteria in Table 2 when 50 ng of 4-bromofluorobenzene
(BFB) is injected through the GC inlet.
5.3.4 GC/MS interface--Any GC to MS interface that gives acceptable
calibration points at 50 ng or less per injection for each of the
parameters of interest and achieves all acceptable performance criteria
(Section 10) may be used. GC to MS interfaces constructed of all glass
or glass-lined materials are recommended. Glass can be deactivated by
silanizing with dichlorodimethylsilane.
5.3.5 Data system--A computer system must be interfaced to the mass
spectrometer that allows the continuous acquisition and storage on
machine-readable media of all mass spectra obtained throughout the
duration of the chromatographic program. The computer must have software
that allows searching any GC/MS data file for specific m/z (masses) and
plotting such m/z abundances versus time or scan number. This type of
plot is defined as an Extracted Ion Current Profile (EICP). Software
must also be available that allows integrating the abundance in any EICP
between specified time or scan number limits.
5.4 Syringes--5-mL, glass hypodermic with Luerlok tip (two each), if
applicable to the purging device.
5.5 Micro syringes--25-[micro]L, 0.006 in. ID needle.
5.6 Syringe valve--2-way, with Luer ends (three each).
5.7 Syringe--5-mL, gas-tight with shut-off valve.
5.8 Bottle--15-mL, screw-cap, with Teflon cap liner.
5.9 Balance--Analytical, capable of accurately weighing 0.0001 g.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.1.1 Reagent water can be generated by passing tap water through a
carbon filter bed containing about 1 lb of activated carbon (Filtrasorb-
300, Calgon Corp., or equivalent).
6.1.2 A water purification system (Millipore Super-Q or equivalent)
may be used to generate reagent water.
6.1.3 Reagent water may also be prepared by boiling water for 15
min. Subsequently, while maintaining the temperature at 90 [deg]C,
bubble a contaminant-free inert gas through the water for 1 h. While
still hot, transfer the water to a narrow mouth screw-cap bottle and
seal with a Teflon-lined septum and cap.
6.2 Sodium thiosulfate--(ACS) Granular.
6.3 Trap materials:
6.3.1 2,6-Diphenylene oxide polymer--Tenax, (60/80 mesh),
chromatographic grade or equivalent.
6.3.2 Methyl silicone packing--3% OV-1 on Chromosorb-W (60/80 mesh)
or equivalent.
[[Page 222]]
6.3.3 Silica gel--35/60 mesh, Davison, grade-15 or equivalent.
6.4 Methanol--Pesticide quality or equivalent.
6.5 Stock standard solutions--Stock standard solutions may be
prepared from pure standard materials or purchased as certified
solutions. Prepare stock standard solutions in methanol using assayed
liquids or gases as appropriate. Because of the toxicity of some of the
compounds, primary dilutions of these materials should be prepared in a
hood. A NIOSH/MESA approved toxic gas respirator should be used when the
analyst handles high concentrations of such materials.
6.5.1 Place about 9.8 mL of methanol into a 10-mL ground glass
stoppered volumetric flask. Allow the flask to stand, unstoppered, for
about 10 min or until all alcohol wetted surfaces have dried. Weigh the
flask to the nearest 0.1 mg.
6.5.2 Add the assayed reference material:
6.5.2.1 Liquids--Using a 100-[micro]L syringe, immediately add two
or more drops of assayed reference material to the flask, then reweigh.
Be sure that the drops fall directly into the alcohol without contacting
the neck of the flask.
6.5.2.2 Gases--To prepare standards for any of the four halocarbons
that boil below 30 [deg]C (bromomethane, chloroethane, chloromethane,
and vinyl chloride), fill a 5-mL valved gas-tight syringe with the
reference standard to the 5.0-mL mark. Lower the needle to 5 mm above
the methanol meniscus. Slowly introduce the reference standard above the
surface of the liquid (the heavy gas will rapidly dissolve in the
methanol).
6.5.3 Reweigh, dilute to volume, stopper, then mix by inverting the
flask several times. Calculate the concentration in [micro]g/[micro]L
from the net gain in weight. When compound purity is assayed to be 96%
or greater, the weight may be used without correction to calculate the
concentration of the stock standard. Commercially prepared stock
standards may be used at any concentration if they are certified by the
manufacturer or by an independent source.
6.5.4 Transfer the stock standard solution into a Teflon-sealed
screw-cap bottle. Store, with minimal headspace, at -10 to -20 [deg]C
and protect from light.
6.5.5 Prepare fresh standards weekly for the four gases and 2-
chloroethylvinyl ether. All other standards must be replaced after one
month, or sooner if comparison with check standards indicates a problem.
6.6 Secondary dilution standards--Using stock solutions, prepare
secondary dilution standards in methanol that contain the compounds of
interest, either singly or mixed together. The secondary dilution
standards should be prepared at concentrations such that the aqueous
calibration standards prepared in Section 7.3 will bracket the working
range of the analytical system. Secondary dilution standards should be
stored with minimal headspace and should be checked frequently for signs
of degradation or evaporation, especially just prior to preparing
calibration standards from them.
6.7 Surrogate standard spiking solution--Select a minimum of three
surrogate compounds from Table 3. Prepare stock standard solutions for
each surrogate standard in methanol as described in Section 6.5. Prepare
a surrogate standard spiking solution from these stock standards at a
concentration of 15 [micro]g/mL in water. Store the solutions at 4
[deg]C in Teflon-sealed glass containers with a minimum of headspace.
The solutions should be checked frequently for stability. The addition
of 10 [micro]L of this solution of 5 mL of sample or standard is
equivalent to a concentration of 30 [micro]g/L of each surrogate
standard.
6.8 BFB Standard--Prepare a 25 [micro]g/mL solution of BFB in
methanol.
6.9 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Assemble a purge and trap system that meets the specifications
in Section 5.2. Condition the trap overnight at 180 [deg]C by
backflushing with an inert gas flow of at least 20 mL/min. Condition the
trap for 10 min once daily prior to use.
7.2 Connect the purge and trap system to a gas chromatograph. The
gas chromatograph must be operated using temperature and flow rate
conditions equivalent to those given in Table 1.
7.3 Internal standard calibration procedure--To use this approach,
the analyst must select three or more internal standards that are
similar in analytical behavior to the compounds of interest. The analyst
must further demonstrate that the measurement of the internal standard
is not affected by method or matrix interferences. Some recommended
internal standards are listed in Table 3.
7.3.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter by carefully adding 20.0
[micro]L of one or more secondary dilution standards to 50, 250, or 500
mL of reagent water. A 25-[micro]L syringe with a 0.006 in. ID needle
should be used for this operation. One of the calibration standards
should be at a concentration near, but above, the MDL (Table 1) and the
other concentrations should correspond to the expected range of
concentrations found in real samples or should define the working range
of the GC/MS system. These aqueous standards can be stored up to 24 h,
if held in sealed vials with zero headspace as described in Section 9.2.
If not so stored, they must be discarded after 1 h.
7.3.2 Prepare a spiking solution containing each of the internal
standards using the procedures described in Sections 6.5 and
[[Page 223]]
6.6. It is recommended that the secondary dilution standard be prepared
at a concentration of 15 [micro]g/mL of each internal standard compound.
The addition of 10 [micro]L of this standard to 5.0 mL of sample or
calibration standard would be equivalent to 30 [micro]g/L.
7.3.3 Analyze each calibration standard according to Section 11,
adding 10 [micro]L of internal standard spiking solution directly to the
syringe (Section 11.4). Tabulate the area response of the characteristic
m/z against concentration for each compound and internal standard, and
calculate response factors (RF) for each compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.124
Equation 1
where:
As=Area of the characteristic m/z for the parameter to be
measured.
Ais=Area of the characteristic m/z for the inernal standard.
Cis=Concentration of the internal standard.
Cs=Concentration of the parameter to be measured.
If the RF value over the working range is a constant (<35% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.4 The working calibration curve or RF must be verified on each
working day by the measurement of a QC check sample.
7.4.1 Prepare the QC check sample as described in Section 8.2.2.
7.4.2 Analyze the QC check sample according to the method beginning
in Section 10.
7.4.3 For each parameter, compare the response (Q) with the
corresponding calibration acceptance criteria found in Table 5. If the
responses for all parameters of interest fall within the designated
ranges, analysis of actual samples can begin. If any individual Q falls
outside the range, proceed according to Section 7.4.4.
Note: The large number of parameters in Table 5 present a
substantial probability that one or more will not meet the calibration
acceptance criteria when all parameters are analyzed.
7.4.4 Repeat the test only for those parameters that failed to meet
the calibration acceptance criteria. If the response for a parameter
does not fall within the range in this second test, a new calibration
curve or RF must be prepared for that parameter according to Section
7.3.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occurring in
chromatography, the analyst is permitted certain options (detailed in
Section 11.1) to improve the separations or lower the cost of
measurements. Each time such a modification is made to the method, the
analyst is required to repeat the procedure in Section 8.2.
8.1.3 Each day, the analyst must analyze a reagent water blank to
demonstrate that interferences from the analytical system are under
control.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 5% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 5% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must spike all samples with surrogate standards
to monitor continuing laboratory performance. This procedure is
described in Section 8.5.
8.1.7 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.6.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 10 [micro]g/
mL in methanol. The QC check sample concentrate must be obtained from
the U.S. Environmental Protection Agency, Environmental Monitoring and
Support Laboratory in Cincinnati, Ohio, if available. If not available
from that source, the QC check sample
[[Page 224]]
concentrate must be obtained from another external source. If not
available from either source above, the QC check sample concentrate must
be prepared by the laboratory using stock standards prepared
independently from those used for calibration.
8.2.2 Prepare a QC check sample to contain 20 [micro]g/L of each
parameter by adding 200 [micro]L of QC check sample concentrate to 100
mL of reagent water.
8.2.3 Analyze four 5-mL aliquots of the well-mixed QC check sample
according to the method beginning in Section 10.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
of interest using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 5. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Table 5 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.3.
8.2.6.2 Beginning with Section 8.2.3, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compounds of interest beginning with Section 8.2.3.
8.3 The laboratory must, on an ongoing basis, spike at least 5% of
the samples from each sample site being monitored to assess accuracy.
For laboratories analyzing 1 to 20 samples per month, at least one
spiked sample per month is required.
8.3.1 The concentration of the spike in the sample should be
determined as follows:
8.3.1.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 20 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.2 Analyze one 5-mL sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second 5-mL sample aliquot with 10
[micro]L of the QC check sample concentrate and analyze it to determine
the concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 5. These acceptance
criteria wer calculated to include an allowance for error in measurement
of both the background and spike concentrations, assuming a spike to
background ratio of 5:1. This error will be accounted for to the extent
that the analyst's spike to background ratio approaches 5:1. \7\ If
spiking was performed at a concentration lower than 20 [micro]g/L, the
analyst must use either the QC acceptance criteria in Table 5, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recoveryof a parameter: (1) Calculate accuracy (X') using the equation
in Table 6, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 6,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T) (2.44(100 S'/T)%. \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required anlaysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory. If the entire list of parameters in Table 5 must be measured
in the sample in Section 8.3, the probability that the analysis of a QC
check standard will be required is high. In this case the QC check
standard should be routinely analyzed with the spiked sample.
8.4.1 Prepare the QC check standard by adding 10 [micro]L of QC
check sample concentrate (Section 8.2.1 or 8.3.2) to 5 mL of reagent
water. The QC check standard needs only to
[[Page 225]]
contain the parameters that failed criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(PS) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (PS) for each
parameter with the corresponding QC acceptance criteria found in Table
5. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As a quality control check, the laboratory must spike all
samples with the surrogate standard spiking solutions as described in
Section 11.4, and calculate the percent recovery of each surrogate
compound.
8.6 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent recovery interval from P--2sp to P +
2sp. If P=90% and sp=10%, for example, the
accuracy interval is expressed as 70-110%. Update the accuracy
assessment for each parameter a regular basis (e.g. after each five to
ten new accuracy measurements).
8.7 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of the samples. Field duplicates may be analyzed to assess the
precision of the environmental measurements. Whenever possible, the
laboratory should analyze standard reference materials and participate
in relevant performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 All samples must be iced or refrigerated from the time of
collection until analysis. If the sample contains residual chlorine, add
sodium thiosulfate preservative (10 mg/40 mL is sufficient for up to 5
ppm Cl2) to the empty sample bottle just prior to shipping to
the sampling site. EPA Methods 330.4 and 330.5 may be used for
measurement of residual chlorine. \8\ Field test kits are available for
this purpose.
9.2 Grab samples must be collected in glass containers having a
total volume of at least 25 mL. Fill the sample bottle just to
overflowing in such a manner that no air bubbles pass through the sample
as the bottle is being filled. Seal the bottle so that no air bubbles
are entrapped in it. If preservative has been added, shake vigorously
for 1 min. Maintain the hermetic seal on the sample bottle until time of
analysis.
9.3 Experimental evidence indicates that some aromatic compounds,
notably benzene, toluene, and ethyl benzene are susceptible to rapid
biological degradation under certain environmental conditions. \3\
Refrigeration alone may not be adequate to preserve these compounds in
wastewaters for more than seven days. For this reason, a separate sample
should be collected, acidified, and analyzed when these aromatics are to
be determined. Collect about 500 mL of sample in a clean container.
Adjust the pH of the sample to about 2 by adding 1+1 HCl while stirring
vigorously, Check pH with narrow range (1.4 to 2.8) pH paper. Fill a
sample container as described in Section 9.2.
9.4 All samples must be analyzed within 14 days of collection. \3\
10. Daily GC/MS Performance Tests
10.1 At the beginning of each day that analyses are to be performed,
the GC/MS system must be checked to see if acceptable performance
criteria are achieved for BFB. \9\ The performance test must be passed
before any samples, blanks, or standards are analyzed, unless the
instrument has met the DFTPP test described in Method 625 earlier in the
day. \10\
10.2 These performance tests require the following instrumental
parameters:
Electron Energy: 70 V (nominal)
Mass Range: 20 to 260 amu
Scan Time: To give at least 5 scans per peak but not to exceed 7 s
per scan.
10.3 At the beginning of each day, inject 2 [micro]L of BFB solution
directly on the column. Alternatively, add 2 [micro]L of BFB solution to
5.0 mL of reagent water or standard solution and analyze the solution
according to section 11. Obtain a background-corrected mass spectrum of
BFB and confirm that all the key m/z criteria in Table 2 are achieved.
If all the criteria are not achieved, the analyst must retune the mass
spectrometer and repeat the test until all criteria are achieved.
11. Sample Purging and Gas Chromatography
11.1 Table 1 summarizes the recommended operating conditions for the
gas chromatograph. Included in this table are retention times and MDL
that can be achieved under these conditions. An example of the
separations achieved by this column is shown in Figure 5. Other packed
columns or chromatographic conditions may be used if the requirements of
Section 8.2 are met.
[[Page 226]]
11.2 After achieving the key m/z abundance criteria in Section 10,
calibrate the system daiy as described in Section 7.
11.3 Adjust the purge gas (helium) flow rate to 40 mL/min. Attach
the trap inlet to the purging device, and set the purge and trap system
to purge (Figure 3). Open the syringe valve located on the purging
device sample introduction needle.
11.4 Allow the sample to come to ambient temperature prior to
introducing it into the syringe. Remove the plunger from a 5-mL syringe
and attach a closed syringe valve. Open the sample bottle (or standard)
and carefully pour the sample into the syringe barrel to just short of
overflowing. Replace the syringe plunger and compress the sample. Open
the syringe valve and vent any residual air while adjusting the sample
volume to 5.0 mL. Since this process of taking an aliquot destroys the
validity of the sample for future analysis, the analyst should fill a
second syringe at this time to protect against possible loss of data.
Add 10.0 [micro]L of the surrogate spiking solution (Section 6.7) and
10.0 [micro]L of the internal standard spiking solution (Section 7.3.2)
through the valve bore, then close the valve. The surrogate and internal
standards may be mixed and added as a single spiking solution.
11.5 Attach the syringe-syringe valve assembly to the syringe valve
on the purging device. Open the syringe valves and inject the sample
into the purging chamber.
11.6 Close both valves and purge the sample for 11.0 0.1 min at ambient temperature.
11.7 After the 11-min purge time, attach the trap to the
chromatograph, adjust the purge and trap system to the desorb mode
(Figure 4), and begin to temperature program the gas chromatograph.
Introduce the trapped materials to the GC column by rapidly heating the
trap to 180 [deg]C while backflushing the trap with an inert gas between
20 and 60 mL/min for 4 min. If rapid heating of the trap cannot be
achieved, the GC cloumn must be used as a secondary trap by cooling it
to 30 [deg]C (subambient temperature, if problems persist) instead of
the initial program temperature of 45 [deg]C.
11.8 While the trap is being desorbed into the gas chromatograph,
empty the purging chamber using the sample introduction syringe. Wash
the chamber with two 5-mL flushes of reagent water.
11.9 After desorbing the sample for 4 min, recondition the trap by
returning the purge and trap system to the purge mode. Wait 15 s then
close the syringe valve on the purging device to begin gas flow through
the trap. The trap temperature should be maintained at 180 [deg]C. After
approximately 7 min, turn off the trap heater and open the syringe valve
to stop the gas flow through the trap. When the trap is cool, the next
sample can be analyzed.
11.10 If the response for any m/z exceeds the working range of the
system, prepare a dilution of the sample with reagent water from the
aliquot in the second syringe and reanalyze.
12. Qualitative Identification
12.1 Obtain EICPs for the primary m/z (Table 4) and at least two
secondary masses for each parameter of interest. The following criteria
must be met to make a qualitative identification:
12.1.1 The characteristic masses of each parameter of interest must
maximize in the same or within one scan of each other.
12.1.2 The retention time must fall within 30
s of the retention time of the authentic compound.
12.1.3 The relative peak heights of the three characteristic masses
in the EICPs must fall within 20% of the relative
intensities of these masses in a reference mass spectrum. The reference
mass spectrum can be obtained from a standard analyzed in the GC/MS
system or from a reference library.
12.2 Structural isomers that have very similar mass spectra and less
than 30 s difference in retention time, can be explicitly identified
only if the resolution between authentic isomers in a standard mix is
acceptable. Acceptable resolution is achieved if the baseline to valley
height between the isomers is less than 25% of the sum of the two peak
heights. Otherwise, structural isomers are identified as isomeric pairs.
13. Calculations
13.1 When a parameter has been identified, the quantitation of that
parameter should be based on the integrated abundance from the EICP of
the primary characteristic m/z given in Table 4. If the sample produces
an interference for the primary m/z, use a secondary characteristic m/z
to quantitate.
Calculate the concentration in the sample using the response factor
(RF) determined in Section 7.3.3 and Equation 2.
[GRAPHIC] [TIFF OMITTED] TC15NO91.125
Equation 2
where:
AS=Area of the characteristic m/z for the parameter or
surrogate standard to be measured.
Ais=Area of the characteristic m/z for the internal standard.
Cis=Concentration of the internal standard.
13.2 Report results in [micro]g/L without correction for recovery
data. All QC data obtained should be reported with the sample results.
[[Page 227]]
14. Method Performance
14.1 The method detection limit (MDL) is defined as the minimum
concentration of a substance that can be measured and reported with 99%
confidence that the value is above zero. \1\ The MDL concentrations
listed in Table 1 were obtained using reagent water. \11\ Similar
results were achieved using representative wastewaters. The MDL actually
achieved in a given analysis will vary depending on instrument
sensitivity and matrix effects.
14.2 This method was tested by 15 laboratories using reagent water,
drinking water, surface water, and industrial wastewaters spiked at six
concentrations over the range 5-600 [micro]g/L. \12\ Single operator
precision, overall precision, and method accuracy were found to be
directly related to the concentration of the parameter and essentially
independent of the sample matrix. Linear equations to describe these
relationships are presented in Table 5.
References
1. 40 CFR part 136, appendix B.
2. Bellar, T.A., and Lichtenberg, J.J. ``Determining Volatile
Organics at Microgram-per-Litre Levels by Gas Chromatography,'' Journal
American Water Works Association, 66, 739 (1974).
3. Bellar, T.A., and Lichtenberg, J.J. ``Semi-Automated Headspace
Analysis of Drinking Waters and Industrial Waters for Purgeable Volatile
Organic Compounds, '' Measurement of Organic Pollutants in Water and
Wastewater, C.E. Van Hall, editor, American Society for Testing and
Materials, Philadelphia, PA. Special Technical Publication 686, 1978.
4. ``Carcinogens--Working With Carcinogens,'' Department of Health,
Education, and Welfare, Public Health Service, Center for Disease
Control, National Institute for Occupational Safety and Health,
Publication No. 77-206, August 1977.
5. ``OSHA Safety and Health Standards, General Industry,'' (29 CFR
part 1910), Occupational Safety and Health Administration, OSHA 2206
(Revised, January 1976).
6. ``Safety in Academic Chemistry Laboratories,'' American Chemical
Society Publication, Committee on Chemical Safety, 3rd Edition, 1979.
7. Provost, L.P., and Elder, R.S. ``Interpretation of Percent
Recovery Data,'' American Laboratory, 15, 58-63 (1983). (The value 2.44
used in the equation in Section 8.2.3 is two times the value 1.22
derived in this report.)
8. ``Methods 330.4 (Titrimetric, DPD-FAS) and 330.5
(Spectrophotometric, DPD) for Chlorine, Total Residual,'' Methods for
Chemical Analysis of Water and Wastes, EPA-600/4-79-020, U.S.
Environmental Protection Agency, Environmental Monitoring and Support
Laboratory, Cincinnati, Ohio 45268, March 1979.
9. Budde, W.L., and Eichelberger, J.W. ``Performance Tests for the
Evaluation of Computerized Eas Chromatography/Mass Spectrometry
Equipment and Laboratories,'' EPA-600/4-80-025, U.S. Environmental
Protection Agency, Environmental Monitoring and Support Laboratory,
Cincinnati, Ohio 45268, April 1980.
10. Eichelberger, J.W., Harris, L.E., and Budde, W.L. ``Reference
Compound to Calibrate Ion Abundance Measurement in Gas Chromatography--
Mass Spectrometry Systems,'' Analytical Chemistry, 47, 995-1000 (1975).
11. ``Method Detection Limit for Methods 624 and 625,'' Olynyk, P.,
Budde, W.L., and Eichelberger, J.W. Unpublished report, May 14, 1980.
12. ``EPA Method Study 29 EPA Method 624--Purgeables,'' EPA 600/4-
84-054, National Technical Information Service, PB84-209915,
Springfield, Virginia 22161, June 1984.
13.``Method Performance Data for Method 624,'' Memorandum from R.
Slater and T. Pressley, U.S. Environmental Protection Agency,
Environmental Monitoring and Support Laboratory, Cincinnati, Ohio 45268,
January 17, 1984.
Table 1--Chromatographic Conditions and Method Detection Limits
------------------------------------------------------------------------
Method
detection
Parameter Retention limit
time (min) ([micro]g/
L)
------------------------------------------------------------------------
Chloromethane................................... 2.3 nd
Bromomethane.................................... 3.1 nd
Vinyl chloride.................................. 3.8 nd
Chloroethane.................................... 4.6 nd
Methylene chloride.............................. 6.4 2.8
Trichlorofluoromethane.......................... 8.3 nd
1,1-Dichloroethene.............................. 9.0 2.8
1,1-Dichloroethane.............................. 10.1 4.7
trans-1,2-Dichloroethene........................ 10.8 1.6
Chloroform...................................... 11.4 1.6
1,2-Dichloroethane.............................. 12.1 2.8
1,1,1-Trichloroethane........................... 13.4 3.8
Carbon tetrachloride............................ 13.7 2.8
Bromodichloromethane............................ 14.3 2.2
1,2-Dichloroproane.............................. 15.7 6.0
cis-1,3-Dichloropropene......................... 15.9 5.0
Trichloroethene................................. 16.5 1.9
Benzene......................................... 17.0 4.4
Dibromochloromethane............................ 17.1 3.1
1,1,2-Trichloroethane........................... 17.2 5.0
trans-1,3-Dichloropropene....................... 17.2 nd
2-Chloroethylvinlyl ether....................... 18.6 nd
Bromoform....................................... 19.8 4.7
1,1,2,2-Tetrachloroethane....................... 22.1 6.9
Tetrachloroethene............................... 22.2 4.1
Toluene......................................... 23.5 6.0
Chlorobenzene................................... 24.6 6.0
Ethyl benzene................................... 26.4 7.2
1,3-Dichlorobenzene............................. 33.9 nd
1,2-Dichlorobenzene............................. 35.0 nd
[[Page 228]]
1,4-Dichlorobenzene............................. 35.4 nd
------------------------------------------------------------------------
Column conditions: Carbopak B (60/80 mesh) coated with 1% SP-1000 packed
in a 6 ft by 0.1 in. ID glass column with helium carrier gas at 30 mL/
min. flow rate. Column temperature held at 45[deg]C for 3 min., then
programmed at 8[deg]C/min. to 220[deg]C and held for 15 min.
nd=not determined.
Table 2--BFB Key m/z Abundance Criteria
------------------------------------------------------------------------
Mass m/z Abundance criteria
------------------------------------------------------------------------
50........................................ 15 to 40% of mass 95.
75........................................ 30 to 60% of mass 95.
95........................................ Base Peak, 100% Relative
Abundance.
96........................................ 5 to 9% of mass 95.
173....................................... <2% of mass 174.
174....................................... 50% of mass 95.
175....................................... 5 to 9% of mass 174.
176....................................... 95% but <101% of
mass 174.
177....................................... 5 to 9% of mass 176.
------------------------------------------------------------------------
Table 3--Suggested Surrogate and Internal Standards
------------------------------------------------------------------------
Retention
Compound time Primary Secondary
(min) \a\ m/z masses
------------------------------------------------------------------------
Benzene d-6............................ 17.0 84 ...........
4-Bromofluorobenzene................... 28.3 95 174, 176
1,2-Dichloroethane d-4................. 12.1 102 ...........
1,4-Difluorobenzene.................... 19.6 114 63, 88
Ethylbenzene d-5....................... 26.4 111 ...........
Ethylbenzene d-10...................... 26.4 98 ...........
Fluorobenzene.......................... 18.4 96 70
Pentafluorobenzene..................... 23.5 168 ...........
Bromochloromethane..................... 9.3 128 49, 130, 51
2-Bromo-1-chloropropane................ 19.2 77 79, 156
1, 4-Dichlorobutane.................... 25.8 55 90, 92
------------------------------------------------------------------------
\a\ For chromatographic conditions, see Table 1.
Table 4--Characteristic Masses for Purgeable Organics
------------------------------------------------------------------------
Parameter Primary Secondary
------------------------------------------------------------------------
Chloromethane........................ 50 52.
Bromomethane......................... 94 96.
Vinyl chloride....................... 62 64.
Chloroethane......................... 64 66.
Methylene chloride................... 84 49, 51, and 86.
Trichlorofluoromethane............... 101 103.
1,1-Dichloroethene................... 96 61 and 98.
1,1-Dichloroethane................... 63 65, 83, 85, 98, and 100.
trans-1,2-Dichloroethene............. 96 61 and 98.
Chloroform........................... 83 85.
1,2-Dichloroethane................... 98 62, 64, and 100.
1,1,1-Trichloroethane................ 97 99, 117, and 119.
Carbon tetrachloride................. 117 119 and 121.
Bromodichloromethane................. 127 83, 85, and 129.
1,2-Dichloropropane.................. 112 63, 65, and 114.
trans-1,3-Dichloropropene............ 75 77.
Trichloroethene...................... 130 95, 97, and 132.
Benzene.............................. 78 ........................
Dibromochloromethane................. 127 129, 208, and 206.
1,1,2-Trichloroethane................ 97 83, 85, 99, 132, and
134.
cis-1,3-Dichloropropene.............. 75 77.
2-Chloroethylvinyl ether............. 106 63 and 65.
Bromoform............................ 173 171, 175, 250, 252, 254,
and 256.
1,1,2,2-Tetrachloroethane............ 168 83, 85, 131, 133, and
166.
Tetrachloroethene.................... 164 129, 131, and 166.
Toluene.............................. 92 91.
Chlorobenzene........................ 112 114.
Ethyl benzene........................ 106 91.
1,3-Dichlorobenzene.................. 146 148 and 113.
1,2-Dichlorobenzene.................. 146 148 and 113.
1,4-Dichlorobenzene.................. 146 148 and 113.
------------------------------------------------------------------------
Table 5--Calibration and QC Acceptance Criteria--Method 624 \a\
----------------------------------------------------------------------------------------------------------------
Limit for
Range for Q s Range for X Range for P,
Parameter ([micro]/g/L) ([micro]/ ([micro]/g/L) Ps (%)
g/L)
----------------------------------------------------------------------------------------------------------------
Benzene.............................................. 12.8-27.2 6.9 15.2-26.0 37-151
Bromodichloromethane................................. 13.1-26.9 6.4 10.1-28.0 35-155
Bromoform............................................ 14.2-25.8 5.4 11.4-31.1 45-169
Bromomethane......................................... 2.8-37.2 17.9 D-41.2 D-242
Carbon tetrachloride................................. 14.6-25.4 5.2 17.2-23.5 70-140
Chlorobenzene........................................ 13.2-26.8 6.3 16.4-27.4 37-160
Chloroethane......................................... 7.6-32.4 11.4 8.4-40.4 14-230
2-Chloroethylvinyl ether............................. D-44.8 25.9 D-50.4 D-305
Chloroform........................................... 13.5-26.5 6.1 13.7-24.2 51-138
Chloromethane........................................ D-40.8 19.8 D-45.9 D-273
Dibromochloromethane................................. 13.5-26.5 6.1 13.8-26.6 53-149
1,2-Dichlorobenzene.................................. 12.6-27.4 7.1 11.8-34.7 18-190
1,3-Dichlorobenzene.................................. 14.6-25.4 5.5 17.0-28.8 59-156
1,4-Dichlorobenzene.................................. 12.6-27.4 7.1 11.8-34.7 18-190
1,1-Dichloroethane................................... 14.5-25.5 5.1 14.2-28.5 59-155
1,2-Dichloroethane................................... 13.6-26.4 6.0 14.3-27.4 49-155
1,1-Dichlorothene.................................... 10.1-29.9 9.1 3.7-42.3 D-234
trans-1,2-Dichloroethene............................. 13.9-26.1 5.7 13.6-28.5 54-156
[[Page 229]]
1,2-Dichloropropane.................................. 6.8-33.2 13.8 3.8-36.2 D-210
cis-1,3-Dichloropropene.............................. 4.8-35.2 15.8 1.0-39.0 D-227
trans-1,3-Dichloropropene............................ 10.0-30.0 10.4 7.6-32.4 17-183
Ethyl benzene........................................ 11.8-28.2 7.5 17.4-26.7 37-162
Methylene chloride................................... 12.1-27.9 7.4 D-41.0 D-221
1,1,2,2-Tetrachloroethane............................ 12.1-27.9 7.4 13.5-27.2 46-157
Tetrachloroethene.................................... 14.7-25.3 5.0 17.0-26.6 64-148
Toluene.............................................. 14.9-25.1 4.8 16.6-26.7 47-150
1,1,1-Trichloroethane................................ 15.0-25.0 4.6 13.7-30.1 52-162
1,1,2-Trichloroethane................................ 14.2-25.8 5.5 14.3-27.1 52-150
Trichloroethene...................................... 13.3-26.7 6.6 18.6-27.6 71-157
Trichlorofluoromethane............................... 9.6-30.4 10.0 8.9-31.5 17-181
Vinyl chloride....................................... 0.8-39.2 20.0 D-43.5 D-251
----------------------------------------------------------------------------------------------------------------
Q= Concentration measured in QC check sample, in [micro]g/L (Section 7.5.3).
s= Standard deviation of four recovery measurements, in [micro]g/L (Section 8.2.4).
X= Average recovery of four recovery measurements, in [micro]g/L (Section 8.2.4).
P, Ps= Percent recovery measured, (Section 8.3.2, Section 8.4.2).
D= Detected; result must be greater than zero.
\a\ Criteria were calculated assuming a QC check sample concentration of 20 [micro]g/L.
Note: These criteria are based directly upon the method performance data in Table 6. Where necessary, the limits
for recovery have been broadened to assure applicability of the limits to concentrations below those used to
develop Table 6.
Table 6--Method Accuracy and Precision as Functions of Concentration--Method 624
----------------------------------------------------------------------------------------------------------------
Single analyst
Parameter Accuracy, as recovery, precision, sr' Overall precision, S'
X' ([micro]g/L) ([micro]g/L) ([micro]g/L)
----------------------------------------------------------------------------------------------------------------
Benzene............................... 0.93C+2.00 0.26X-1.74 0.25X-1.33
Bromodichloromethane.................. 1.03C-1.58 0.15X+0.59 0.20X+1.13
Bromoform............................. 1.18C-2.35 0.12X+0.36 0.17X+1.38
Bromomethane \a\...................... 1.00C 0.43X 0.58X
Carbon tetrachloride.................. 1.10C-1.68 0.12X+0.25 0.11X+0.37
Chlorobenzene......................... 0.98C+2.28 0.16X-0.09 0.26X-1.92
Chloroethane.......................... 1.18C+0.81 0.14X+2.78 0.29X+1.75
2-Chloroethylvinyl ether \a\.......... 1.00C 0.62X 0.84X
Chloroform............................ 0.93C+0.33 0.16X+0.22 0.18X+0.16
Chloromethane......................... 1.03C+0.81 0.37X+2.14 0.58X+0.43
Dibromochloromethane.................. 1.01C-0.03 0.17X-0.18 0.17X+0.49
1,2-Dichlorobenzene \b\............... 0.94C+4.47 0.22X-1.45 0.30X-1.20
1,3-Dichlorobenzene................... 1.06C+1.68 0.14X-0.48 0.18X-0.82
1,4-Dichlorobenzene \b\............... 0.94C+4.47 0.22X-1.45 0.30X-1.20
1,1-Dichloroethane.................... 1.05C+0.36 0.13X-0.05 0.16X+0.47
1,2-Dichloroethane.................... 1.02C+0.45 0.17X-0.32 0.21X-0.38
1,1-Dichloroethene.................... 1.12C+0.61 0.17X+1.06 0.43X-0.22
trans-1,2,-Dichloroethene............. 1.05C+0.03 0.14X+0.09 0.19X+0.17
1,2-Dichloropropane \a\............... 1.00C 0.33X 0.45X
cis-1,3-Dichloropropene \a\........... 1.00C 0.38X 0.52X
trans-1,3-Dichloropropene \a\......... 1.00C 0.25X 0.34X
Ethyl benzene......................... 0.98C+2.48 0.14X+1.00 0.26X-1.72
Methylene chloride.................... 0.87C+1.88 0.15X+1.07 0.32X+4.00
1,1,2,2-Tetrachloroethane............. 0.93C+1.76 0.16X+0.69 0.20X+0.41
Tetrachloroethene..................... 1.06C+0.60 0.13X-0.18 0.16X-0.45
Toluene............................... 0.98C+2.03 0.15X-0.71 0.22X-1.71
1,1,1-Trichloroethane................. 1.06C+0.73 0.12X-0.15 0.21X-0.39
1,1,2-Trichloroethane................. 0.95C+1.71 0.14X+0.02 0.18X+0.00
Trichloroethene....................... 1.04C+2.27 0.13X+0.36 0.12X+0.59
Trichloroflouromethane................ 0.99C+0.39 0.33X-1.48 0.34X-0.39
Vinyl chloride........................ 1.00C 0.48X 0.65X
----------------------------------------------------------------------------------------------------------------
X'=Expected recovery for one or more measurements of a sample containing a concentration of C, in [micro]g/L.
S\r\=Expected single analyst standard deviation of measurements at an average concentration found ofX, in
[micro]g/L.
S'=Expected interlaboratory standard deviation of measurements at an average concentration found ofX, in
[micro]g/L.
C=True value for the concentration, in [micro]g/L.
X=Average recovery found for measurements of samples containing a concentration of C, in [micro]g/L.
\a\ Estimates based upon the performance in a single laboratory. \13\
\b\ Due to chromatographic resolution problems, performance statements for these isomers are based upon the sums
of their concentrations.
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[GRAPHIC] [TIFF OMITTED] TC02JY92.039
[[Page 232]]
[GRAPHIC] [TIFF OMITTED] TC02JY92.040
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[GRAPHIC] [TIFF OMITTED] TC02JY92.041
Method 625--Base/Neutrals and Acids
1. Scope and Application
1.1 This method covers the determination of a number of organic
compounds that are partitioned into an organic solvent and are amenable
to gas chromatography. The parameters listed in Tables 1 and 2 may be
qualitatively and quantitatively determined using this method.
1.2 The method may be extended to include the parameters listed in
Table 3. Benzidine can be subject to oxidative losses during solvent
concentration. Under the alkaline conditions of the extraction step,
[alpha]-BHC, [gamma]-BHC, endosulfan I and II, and endrin are subject to
decomposition. Hexachlorocyclopentadiene is subject to thermal
decomposition in the inlet of the gas chromatograph, chemical reaction
in acetone solution, and photochemical decomposition. N-
nitrosodimethylamine is difficult to separate from the solvent under the
chromatographic conditions described. N-nitrosodiphenylamine decomposes
in the gas chromatographic inlet and cannot be separated from
diphenylamine. The preferred method for each of these parameters is
listed in Table 3.
1.3 This is a gas chromatographic/mass spectrometry (GC/MS) method
\2,14\ applicable to the determination of the compounds listed in Tables
1, 2, and 3 in municipal and industrial discharges as provided under 40
CFR 136.1.
[[Page 234]]
1.4 The method detection limit (MDL, defined in Section 16.1) \1\
for each parameter is listed in Tables 4 and 5. The MDL for a specific
wastewater may differ from those listed, depending upon the nature of
interferences in the sample matrix.
1.5 Any modification to this method, beyond those expressly
permitted, shall be considered as a major modification subject to
application and approval of alternate test procedures under 40 CFR 136.4
and 136.5. Depending upon the nature of the modification and the extent
of intended use, the applicant may be required to demonstrate that the
modifications will produce equivalent results when applied to relevant
wastewaters.
1.6 This method is restricted to use by or under the supervision of
analysts experienced in the use of a gas chromatograph/mass spectrometer
and in the interpretation of mass spectra. Each analyst must demonstrate
the ability to generate acceptable results with this method using the
procedure described in Section 8.2.
2. Summary of Method
2.1 A measured volume of sample, approximately 1-L, is serially
extracted with methylene chloride at a pH greater than 11 and again at a
pH less than 2 using a separatory funnel or a continuous extractor. \2\
The methylene chloride extract is dried, concentrated to a volume of 1
mL, and analyzed by GC/MS. Qualitative identification of the parameters
in the extract is performed using the retention time and the relative
abundance of three characteristic masses (m/z). Quantitative analysis is
performed using internal standard techniques with a single
characteristic m/z.
3. Interferences
3.1 Method interferences may be caused by contaminants in solvents,
reagents, glassware, and other sample processing hardware that lead to
discrete artifacts and/or elevated baselines in the total ion current
profiles. All of these materials must be routinely demonstrated to be
free from interferences under the conditions of the analysis by running
laboratory reagent blanks as described in Section 8.1.3.
3.1.1 Glassware must be scrupulously cleaned. \3\ Clean all
glassware as soon as possible after use by rinsing with the last solvent
used in it. Solvent rinsing should be followed by detergent washing with
hot water, and rinses with tap water and distilled water. The glassware
should then be drained dry, and heated in a muffle furnace at 400 [deg]C
for 15 to 30 min. Some thermally stable materials, such as PCBs, may not
be eliminated by this treatment. Solvent rinses with acetone and
pesticide quality hexane may be substituted for the muffle furnace
heating. Thmrough rinsing with such solvents usually eliminates PCB
interference. Volumetric ware should not be heated in a muffle furnace.
After drying and cooling, glassware should be sealed and stored in a
clean environment to prevent any accumulation of dust or other
contaminants. Store inverted or capped with aluminum foil.
3.1.2 The use of high purity reagents and solvents helps to minimize
interference problems. Purification of solvents by distillation in all-
glass systems may be required.
3.2 Matrix interferences may be caused by contaminants that are co-
extracted from the sample. The extent of matrix interferences will vary
considerably from source to source, depending upon the nature and
diversity of the industrial complex or municipality being sampled.
3.3 The base-neutral extraction may cause significantly reduced
recovery of phenol, 2-methylphenol, and 2,4-dimethylphenol. The analyst
must recognize that results obtained under these conditions are minimum
concentrations.
3.4 The packed gas chromatographic columns recommended for the basic
fraction may not exhibit sufficient resolution for certain isomeric
pairs including the following: anthracene and phenanthrene; chrysene and
benzo(a)anthracene; and benzo(b)fluoranthene and benzo(k)fluoranthene.
The gas chromatographic retention time and mass spectra for these pairs
of compounds are not sufficiently different to make an unambiguous
identification. Alternative techniques should be used to identify and
quantify these specific compounds, such as Method 610.
3.5 In samples that contain an inordinate number of interferences,
the use of chemical ionization (CI) mass spectrometry may make
identification easier. Tables 6 and 7 give characteristic CI ions for
most of the compounds covered by this method. The use of CI mass
spectrometry to support electron ionization (EI) mass spectrometry is
encouraged but not required.
4. Safety
4.1 The toxicity or carcinogenicity of each reagent used in this
method have not been precisely defined; however, each chemical compound
should be treated as a potential health hazard. From this viewpoint,
exposure to these chemicals must be reduced to the lowest possible level
by whatever means available. The laboratory is responsible for
maintaining a current awareness file of OSHA regulations regarding the
safe handling of the chemicals specified in this method. A reference
file of material data handling sheets should also be made available to
all personnel involved in the chemical analysis. Additional references
to laboratory safety are available and have been identified
4-6 for the information of the analyst.
[[Page 235]]
4.2 The following parameters covered by this method have been
tentatively classified as known or suspected, human or mammalian
carcinogens: benzo(a)anthracene, benzidine, 3,3'-dichlorobenzidine,
benzo(a)pyrene, [alpha]-BHC, [beta]-BHC, [delta]-BHC, [gamma]-BHC,
dibenzo(a,h)anthracene, N-nitrosodimethylamine, 4,4'-DDT, and
polychlorinated biphenyls (PCBs). Primary standards of these toxic
compounds should be prepared in a hood. A NIOSH/MESA approved toxic gas
respirator should be worn when the analyst handles high concentrations
of these toxic compounds.
5. Apparatus and Materials
5.1 Sampling equipment, for discrete or composit sampling.
5.1.1 Grab sample bottle--1-L or 1-gt, amber glass, fitted with a
screw cap lined with Teflon. Foil may be substituted for Teflon if the
sample is not corrosive. If amber bottles are not available, protect
samples from light. The bottle and cap liner must be washed, rinsed with
acetone or methylene chloride, and dried before use to minimize
contamination.
5.1.2 Automatic sampler (optional)--The sampler must incorporate
glass sample containers for the collection of a minimum of 250 mL of
sample. Sample containers must be kept refrigerated at 4 [deg]C and
protected from light during compositing. If the sampler uses a
peristaltic pump, a minimum length of compressible silicone rubber
tubing may be used. before use, however, the compressible tubing should
be throughly rinsed with methanol, followed by repeated rinsings with
distilled water to minimize the potential for contamination of the
sample. An integrating flow meter is required to collect flow
proportional composites.
5.2 Glassware (All specifications are suggested. Catalog numbers are
included for illustration only.):
5.2.1 Separatory funnel--2-L, with Teflon stopcock.
5.2.2 Drying column--Chromatographic column, 19 mm ID, with coarse
frit
5.2.3 Concentrator tube, Kuderna-Danish--10-mL, graduated (Kontes K-
570050-1025 or equivalent). Calibration must be checked at the volumes
employed in the test. Ground glass stopper is used to prevent
evaporation of extracts.
5.2.4 Evaporative flask, Kuderna-Danish--500-mL (Kontes K-57001-0500
or equivalent). Attach to concentrator tube with springs.
5.2.5 Snyder column, Kuderna-Danish--Three all macro (Kontes K-
503000-0121 or equivalent).
5.2.6 Snyder column, Kuderna-Danish--Two-ball macro (Kontes K-
569001-0219 or equivalent).
5.2.7 Vials--10 to 15-mL, amber glass, with Teflon-lined screw cap.
5.2.8 Continuous liquid--liquid extractor--Equipped with Teflon or
glass connecting joints and stopcocks requiring no lubrication.
(Hershberg-Wolf Extractor, Ace Glass Company, Vineland, N.J., P/N 6841-
10 or equivalent.)
5.3 Boiling chips--Approximately 10/40 mesh. Heat to 400 [deg]C for
30 min of Soxhlet extract with methylene chloride.
5.4 Water bath--Heated, with concentric ring cover, capable of
temperature control (2[deg]C). The bath should be
used in a hood.
5.5 Balance--Analytical, capable of accurately weighing 0.0001 g.
5.6 GC/MS system:
5.6.1 Gas Chromatograph--An analytical system complete with a
temperature programmable gas chromatograph and all required accessores
including syringes, analytical columns, and gases. The injection port
must be designed for on-column injection when using packed columns and
for splitless injection when using capillary columns.
5.6.2 Column for base/neutrals--1.8 m long x 2 mm ID glass, packed
with 3% SP-2250 on Supelcoport (100/120 mesh) or equivalent. This column
was used to develop the method performance statements in Section 16.
Guidelines for the use of alternate column packings are provided in
Section 13.1.
5.6.3 Column for acids--1.8 m long x 2 mm ID glass, packed with 1%
SP-1240DA on Supelcoport (100/120 mesh) or equivalent. This column was
used to develop the method performance statements in Section 16.
Guidelines for the use of alternate column packings are given in Section
13.1.
5.6.4 Mass spectrometer--Capable of scanning from 35 to 450 amu
every 7 s or less, utilizing a 70 V (nominal) electron energy in the
electron impact ionization mode, and producing a mass spectrum which
meets all the criteria in Table 9 when 50 ng of decafluorotriphenyl
phosphine (DFTPP; bis(perfluorophenyl) phenyl phosphine) is injected
through the GC inlet.
5.6.5 GC/MS interface--Any GC to MS interface that gives acceptable
calibration points at 50 ng per injection for each of the parameters of
interest and achieves all acceptable performance criteria (Section 12)
may be used. GC to MS interfaces constructed of all glass or glass-lined
materials are recommended. Glass can be deactivated by silanizing with
dichlorodimethylsilane.
5.6.6 Data system--A computer system must be interfaced to the mass
spectrometer that allows the contiluous acquisition and storage on
machine-readable media of all mass spectra obtained throughout the
duration of the chromatographic program. The computer must have software
that allows searching any GC/MS data file for specific m/z and plotting
such m/z abundances versus time or scan number. This type of plot is
defined as an Extracted Ion Current Profile (EICP). Software must also
be available that
[[Page 236]]
allows integrating the abundance in any EICP between specified time or
scan number limits.
6. Reagents
6.1 Reagent water--Reagent water is defined as a water in which an
interferent is not observed at the MDL of the parameters of interest.
6.2 Sodium hydroxide solution (10 N)--Dissolve 40 g of NaOH (ACS) in
reagent water and dilute to 100 mL.
6.3 Sodium thiosulfate--(ACS) Granular.
6.4 Sulfuric acid (1+1)--Slowly, add 50 mL of
H2SO4 (ACS, sp. gr. 1.84) to 50 mL of reagent
water.
6.5 Acetone, methanol, methlylene chloride--Pesticide quality or
equivalent.
6.6 Sodium sulfate--(ACS) Granular, anhydrous. Purify by heating at
400 [deg]C for 4 h in a shallow tray.
6.7 Stock standard solutions (1.00 [micro]g/[micro]L)--standard
solutions can be prepared from pure standard materials or purchased as
certified solutions.
6.7.1 Prepare stock standard solutions by accurately weighing about
0.0100 g of pure material. Dissolve the material in pesticide quality
acetone or other suitable solvent and dilute to volume in a 10-mL
volumetric flask. Larger volumes can be used at the convenience of the
analyst. When compound purity is assayed to be 96% or greater, the
weight may be used without correction to calculate the concentration of
the stock standard. Commercially prepared stock standards may be used at
any concentration if they are certified by the manufacturer or by an
independent source.
6.7.2 Transfer the stock standard solutions into Teflon-sealed
screw-cap bottles. Store at 4 [deg]C and protect from light. Stock
standard solutions should be checked frequently for signs of degradation
or evaporation, especially just prior to preparing calibration standards
from them.
6.7.3 Stock standard solutions must be replaced after six months, or
sooner if comparison with quality control check samples indicate a
problem.
6.8 Surrogate standard spiking solution--Select a minimum of three
surrogate compounds from Table 8. Prepare a surrogate standard spiking
solution containing each selected surrogate compound at a concentration
of 100 [micro]g/mL in acetone. Addition of 1.00 mL of this solution to
1000 mL of sample is equivalent to a concentration of 100 [micro]g/L of
each surrogate standard. Store the spiking solution at 4 [deg]C in
Teflon-sealed glass container. The solution should be checked frequently
for stability. The solution must be replaced after six months, or sooner
if comparison with quality control check standards indicates a problem.
6.9 DFTPP standard--Prepare a 25 [micro]g/mL solution of DFTPP in
acetone.
6.10 Quality control check sample concentrate--See Section 8.2.1.
7. Calibration
7.1 Establish gas chromatographic operating parameters equivalent to
those indicated in Table 4 or 5.
7.2 Internal standard calibration procedure--To use this approach,
the analyst must select three or more internal standards that are
similar in analytical behavior to the compounds of interest. The analyst
must further demonstrate that the measurement of the internal standards
is not affected by method or matrix interferences. Some recommended
internal standards are listed in Table 8. Use the base peak m/z as the
primary m/z for quantification of the standards. If interferences are
noted, use one of the next two most intense m/z quantities for
quantification.
7.2.1 Prepare calibration standards at a minimum of three
concentration levels for each parameter of interest by adding
appropriate volumes of one or more stock standards to a volumetric
flask. To each calibration standard or standard mixture, add a known
constant amount of one or more internal standards, and dilute to volume
with acetone. One of the calibration standards should be at a
concentration near, but above, the MDL and the other concentrations
should correspond to the expected range of concentrations found in real
samples or should define the working range of the GC/MS system.
7.2.2 Using injections of 2 to 5 [micro]L, analyze each calibration
standard according to Section 13 and tabulate the area of the primary
characteristic m/z (Tables 4 and 5) against concentration for each
compound and internal standard. Calculate response factors (RF) for each
compound using Equation 1.
[GRAPHIC] [TIFF OMITTED] TC15NO91.126
Equation 1
where:
As=Area of the characteristic m/z for the parameter to be
measured.
Ais=Area of the characteristic m/z for the internal standard.
Cis=Concentration of the internal standard ([micro]g/L).
Cs=Concentration of the parameter to be measured ([micro]g/
L).
If the RF value over the working range is a constant (<35% RSD), the RF
can be assumed to be invariant and the average RF can be used for
calculations. Alternatively, the results can be used to plot a
calibration curve of response ratios, As/Ais, vs.
RF.
7.3 The working calibration curve or RF must be verified on each
working day by the
[[Page 237]]
measurement of one or more calibration standards. If the response for
any parameter varies from the predicted response by more than 20%, the test must be repeated uning a fresh calibration
standard. Alternatively, a new calibration curve must be prepared for
that compound.
8. Quality Control
8.1 Each laboratory that uses this method is required to operate a
formal quality control program. The minimum requirements of this program
consist of an initial demonstration of laboratory capability and an
ongoing analysis of spiked samples to evaluate and document data
quality. The laboratory must maintain records to document the quality of
data that is generated. Ongoing data quality checks are compared with
established performance criteria to determine if the results of analyses
meet the performance characteristics of the method. When results of
sample spikes indicate atypical method performance, a quality control
check standard must be analyzed to confirm that the measurements were
performed in an in-control mode of operation.
8.1.1 The analyst must make an initial, one-time, demonstration of
the ability to generate acceptable accuracy and precision with this
method. This ability is established as described in Section 8.2.
8.1.2 In recognition of advances that are occuring in
chromatography, the analyst is permitted certain options (detailed in
Sections 10.6 and 13.1) to improve the separations or lower the cost of
measurements. Each time such a modification is made to the method, the
analyst is required to repeat the procedure in Section 8.2.
8.1.3 Before processing any samples, the analyst must analyze a
reagent water blank to demonstrate that interferences from the
analytical system and glassware are under control. Each time a set of
samples is extracted or reagents are changed, a reagent water blank must
be processed as a safeguard against laboratory contamination.
8.1.4 The laboratory must, on an ongoing basis, spike and analyze a
minimum of 5% of all samples to monitor and evaluate laboratory data
quality. This procedure is described in Section 8.3.
8.1.5 The laboratory must, on an ongoing basis, demonstrate through
the analyses of quality control check standards that the operation of
the measurement system is in control. This procedure is described in
Section 8.4. The frequency of the check standard analyses is equivalent
to 5% of all samples analyzed but may be reduced if spike recoveries
from samples (Section 8.3) meet all specified quality control criteria.
8.1.6 The laboratory must maintain performance records to document
the quality of data that is generated. This procedure is described in
Section 8.5.
8.2 To establish the ability to generate acceptable accuracy and
precision, the analyst must perform the following operations.
8.2.1 A quality control (QC) check sample concentrate is required
containing each parameter of interest at a concentration of 100
[micro]g/mL in acetone. Multiple solutions may be required. PCBs and
multicomponent pesticides may be omitted from this test. The QC check
sample concentrate must be obtained from the U.S. Environmental
Protection Agency, Environmental Monitoring and Support Laboratory in
Cincinnati, Ohio, if available. If not available from that source, the
QC check sample concentrate must be obtained from another external
source. If not available from either source above, the QC check sample
concentrate must be prepared by the laboratory using stock standards
prepared independently from those used for calibration.
8.2.2 Using a pipet, prepare QC check samples at a concentration of
100 [micro]g/L by adding 1.00 mL of QC check sample concentrate to each
of four 1-L aliquots of reagent water.
8.2.3 Analyze the well-mixed QC check samples according to the
method beginning in Section 10 or 11.
8.2.4 Calculate the average recovery (X) in [micro]g/L, and the
standard deviation of the recovery (s) in [micro]g/L, for each parameter
using the four results.
8.2.5 For each parameter compare s and X with the corresponding
acceptance criteria for precision and accuracy, respectively, found in
Table 6. If s and X for all parameters of interest meet the acceptance
criteria, the system performance is acceptable and analysis of actual
samples can begin. If any individual s exceeds the precision limit or
any individual X falls outside the range for accuracy, the system
performance is unacceptable for that parameter.
Note: The large number of parameters in Table 6 present a
substantial probability that one or more will fail at least one of the
acceptance criteria when all parameters are analyzed.
8.2.6 When one or more of the parameters tested fail at least one of
the acceptance criteria, the analyst must proceed according to Section
8.2.6.1 or 8.2.6.2.
8.2.6.1 Locate and correct the source of the problem and repeat the
test for all parameters of interest beginning with Section 8.2.2.
8.2.6.2 Beginning with Section 8.2.2, repeat the test only for those
parameters that failed to meet criteria. Repeated failure, however, will
confirm a general problem with the measurement system. If this occurs,
locate and correct the source of the problem and repeat the test for all
compounds of interest beginning with Section 8.2.2.
8.3 The laboratory must, on an ongoing basis, spike at least 5% of
the samples from each sample site being monitored to assess
[[Page 238]]
accuracy. For laboratories analyzing 1 to 20 samples per month, at least
one spiked sample per month is required.
8.3.1. The concentration of the spike in the sample should be
determined as follows:
8.3.1 If, as in compliance monitoring, the concentration of a
specific parameter in the sample is being checked against a regulatory
concentration limit, the spike should be at that limit or 1 to 5 times
higher than the background concentration determined in Section 8.3.2,
whichever concentration would be larger.
8.3.1.2 If the concentration of a specific parameter in the sample
is not being checked against a limit specific to that parameter, the
spike should be at 100 [micro]g/L or 1 to 5 times higher than the
background concentration determined in Section 8.3.2, whichever
concentration would be larger.
8.3.1.3 If it is impractical to determine background levels before
spiking (e.g., maximum holding times will be exceeded), the spike
concentration should be (1) the regulatory concentration limit, if any;
or, if none (2) the larger of either 5 times higher than the expected
background concentration or 100 [micro]g/L.
8.3.2 Analyze one sample aliquot to determine the background
concentration (B) of each parameter. If necessary, prepare a new QC
check sample concentrate (Section 8.2.1) appropriate for the background
concentrations in the sample. Spike a second sample aliquot with 1.0 mL
of the QC check sample concentrate and analyze it to determine the
concentration after spiking (A) of each parameter. Calculate each
percent recovery (P) as 100(A-B)%/T, where T is the known true value of
the spike.
8.3.3 Compare the percent recovery (P) for each parameter with the
corresponding QC acceptance criteria found in Table 6. These acceptance
criteria were calculated to include an allowance for error in
measurement of both the background and spike concentrations, assuming a
spike to background ratio of 5:1. This error will be accounted for to
the extent that the analyst's spike to background ratio approaches 5:1.
\7\ If spiking was performed at a concentration lower than 100 [micro]g/
L, the analyst must use either the QC acceptance criteria in Table 6, or
optional QC acceptance criteria calculated for the specific spike
concentration. To calculate optional acceptance criteria for the
recovery of a parameter: (1) Calculate accuracy (X') using the equation
in Table 7, substituting the spike concentration (T) for C; (2)
calculate overall precision (S') using the equation in Table 7,
substituting X' for X; (3) calculate the range for recovery at the spike
concentration as (100 X'/T)2.44(100 S'/T)% \7\
8.3.4 If any individual P falls outside the designated range for
recovery, that parameter has failed the acceptance criteria. A check
standard containing each parameter that failed the criteria must be
analyzed as described in Section 8.4.
8.4 If any parameter fails the acceptance criteria for recovery in
Section 8.3, a QC check standard containing each parameter that failed
must be prepared and analyzed.
Note: The frequency for the required analysis of a QC check standard
will depend upon the number of parameters being simultaneously tested,
the complexity of the sample matrix, and the performance of the
laboratory. If the entire list of single-component parameters in Table 6
must be measured in the sample in Section 8.3, the probability that the
analysis of a QC check standard will be required is high. In this case
the QC check standard should be routinely analyzed with the spike
sample.
8.4.1 Prepare the QC check standard by adding 1.0 mL of QC check
sample concentrate (Section 8.2.1 or 8.3.2) to 1 L of reagent water. The
QC check standard needs only to contain the parameters that failed
criteria in the test in Section 8.3.
8.4.2 Analyze the QC check standard to determine the concentration
measured (A) of each parameter. Calculate each percent recovery
(PS) as 100 (A/T)%, where T is the true value of the standard
concentration.
8.4.3 Compare the percent recovery (Ps) for each
parameter with the corresponding QC acceptance criteria found in Table
6. Only parameters that failed the test in Section 8.3 need to be
compared with these criteria. If the recovery of any such parameter
falls outside the designated range, the laboratory performance for that
parameter is judged to be out of control, and the problem must be
immediately identified and corrected. The analytical result for that
parameter in the unspiked sample is suspect and may not be reported for
regulatory compliance purposes.
8.5 As part of the QC program for the laboratory, method accuracy
for wastewater samples must be assessed and records must be maintained.
After the analysis of five spiked wastewater samples as in Section 8.3,
calculate the average percent recovery (P) and the standard deviation of
the percent recovery (sp). Express the accuracy assessment as
a percent interval from P-2sp to P+2sp. If P=90%
and sp=10%, for example, the accuracy interval is expressed
as 70-110%. Update the accuracy assessment for each parameter on a
regular basis (e.g. after each five to ten new accuracy measurements).
8.6 As a quality control check, the laboratory must spike all
samples with the surrogate standard spiking solution as described in
Section 10.2, and calculate the percent recovery of each surrogate
compound.
8.7 It is recommended that the laboratory adopt additional quality
assurance practices for use with this method. The specific practices
that are most productive depend upon the needs of the laboratory and the
nature of
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the samples. Field duplicates may be analyzed to assess the precision of
the environmental measurements. Whenever possible, the laboratory should
analyze standard reference materials and participate in relevant
performance evaluation studies.
9. Sample Collection, Preservation, and Handling
9.1 Grab samples must be collected in glass containers. Conventional
sampling practices \8\ should be followed, except that the bottle must
not be prerinsed with sample before collection. Composite samples should
be collected in refrigerated glass containers in accordance with the
requirements of the program. Automatic sampling equipment must be as
free as possible of Tygon tubing and other potential sources of
contamination.
9.2 All sampling must be iced or refrigerated at 4 [deg]C from the
time of collection until extraction. Fill the sample bottles and, if
resi